Introduces a new framework for evaluating measurement values against reference ranges and displays this information in the UI.

android_app/app/build.gradle.kts

@@ -146,6 +146,7 @@ dependencies {
     implementation(libs.androidx.ui.graphics)
     implementation(libs.androidx.ui.tooling.preview)
     implementation(libs.androidx.material3)
+    implementation(libs.androidx.constraintlayout.compose)
     implementation(libs.androidx.navigation.compose)
     implementation(libs.androidx.worker)
     implementation(libs.androidx.documentfile)

android_app/app/src/main/java/com/health/openscale/core/data/Enums.kt

@@ -65,6 +65,7 @@ import androidx.compose.material.icons.filled.SquareFoot
 import androidx.compose.material.icons.filled.StackedLineChart
 import androidx.compose.material.icons.filled.Timer
 import androidx.compose.material.icons.filled.WarningAmber
+import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.vector.ImageVector
 import com.health.openscale.R
 import java.util.Locale
@@ -364,4 +365,18 @@ enum class BackupInterval {
              MONTHLY -> context.getString(R.string.interval_monthly)
          }
     }
+}
+
+enum class EvaluationState {
+    LOW,
+    NORMAL,
+    HIGH,
+    UNDEFINED;
+
+    fun toColor(): Color = when (this) {
+        LOW       -> Color(0xFFEF5350) // Red 400
+        NORMAL    -> Color(0xFF66BB6A) // Green 400
+        HIGH      -> Color(0xFFFFA726) // Orange 400
+        UNDEFINED -> Color(0xFFBDBDBD) // Grey 400
+    }
 }

android_app/app/src/main/java/com/health/openscale/core/database/DatabaseRepository.kt

@@ -374,6 +374,11 @@ class DatabaseRepository(
         // User's height is assumed to be stored in CM in the User object
         val userHeightCm = user.heightCm
 
+        val ageAtMeasurementYears = CalculationUtil.ageOn(
+            dateMillis = measurement.timestamp,
+            birthDateMillis = user.birthDate
+        )
+
         // --- PERFORM DERIVED VALUE CALCULATIONS ---
         // Pass the converted values (e.g., weightKg, waistCm) to the processing functions
 
@@ -381,13 +386,23 @@ class DatabaseRepository(
         processLbmCalculation(weightKg, bodyFatPercentage).also { saveOrUpdateDerivedValue(it, MeasurementTypeKey.LBM) }
         processWhrCalculation(waistCm, hipsCm).also { saveOrUpdateDerivedValue(it, MeasurementTypeKey.WHR) }
         processWhtrCalculation(waistCm, userHeightCm).also { saveOrUpdateDerivedValue(it, MeasurementTypeKey.WHTR) }
-        processBmrCalculation(weightKg, user).also { bmr -> // user object contains heightCm and other necessary details
+        processBmrCalculation(
+            weightKg = weightKg,
+            heightCm = user.heightCm,
+            ageYears = ageAtMeasurementYears,
+            gender = user.gender
+        ).also { bmr ->
             saveOrUpdateDerivedValue(bmr, MeasurementTypeKey.BMR)
-            // TDEE calculation depends on the BMR result
             processTDEECalculation(bmr, user.activityLevel).also { saveOrUpdateDerivedValue(it, MeasurementTypeKey.TDEE) }
         }
-        processFatCaliperCalculation(caliper1Cm, caliper2Cm, caliper3Cm, user)
-            .also { saveOrUpdateDerivedValue(it, MeasurementTypeKey.CALIPER) }
+
+        processFatCaliperCalculation(
+            caliper1Cm = caliper1Cm,
+            caliper2Cm = caliper2Cm,
+            caliper3Cm = caliper3Cm,
+            ageYears = ageAtMeasurementYears,
+            gender = user.gender
+        ).also { saveOrUpdateDerivedValue(it, MeasurementTypeKey.CALIPER) }
 
         LogManager.i(DERIVED_VALUES_TAG, "Finished recalculation of derived values for measurementId: $measurementId")
     }
@@ -443,31 +458,25 @@ class DatabaseRepository(
         }
     }
 
-    private fun processBmrCalculation(weightKg: Float?, user: User): Float? {
-        LogManager.v(CALC_PROCESS_TAG, "Processing BMR for user ${user.id}: weight=$weightKg kg")
-        val heightCm = user.heightCm
-        val birthDateTimestamp = user.birthDate
-        val gender = user.gender
+    private fun processBmrCalculation(
+        weightKg: Float?,
+        heightCm: Float?,
+        ageYears: Int,
+        gender: GenderType
+    ): Float? {
+        LogManager.v(CALC_PROCESS_TAG, "Processing BMR: weight=$weightKg kg, height=$heightCm cm, age=$ageYears, gender=$gender")
 
         if (weightKg == null || weightKg <= 0f ||
             heightCm == null || heightCm <= 0f ||
-            birthDateTimestamp <= 0L
+            ageYears !in 1..120
         ) {
-            LogManager.d(CALC_PROCESS_TAG, "BMR calculation skipped: Missing or invalid weight, height, birthdate, or gender.")
+            LogManager.d(CALC_PROCESS_TAG, "BMR calculation skipped: Missing/invalid weight, height or age ($ageYears).")
             return null
         }
 
-        val ageYears = CalculationUtil.dateToAge(birthDateTimestamp)
-        LogManager.v(CALC_PROCESS_TAG, "Calculated age for BMR: $ageYears years")
-
-        return if (ageYears in 1..120) {
-            when (gender) {
-                GenderType.MALE -> (10.0f * weightKg) + (6.25f * heightCm) - (5.0f * ageYears) + 5.0f
-                GenderType.FEMALE -> (10.0f * weightKg) + (6.25f * heightCm) - (5.0f * ageYears) - 161.0f
-            }
-        } else {
-            LogManager.w(CALC_PROCESS_TAG, "Invalid age for BMR calculation: $ageYears years. User ID: ${user.id}")
-            null
+        return when (gender) {
+            GenderType.MALE   -> (10.0f * weightKg) + (6.25f * heightCm) - (5.0f * ageYears) + 5.0f
+            GenderType.FEMALE -> (10.0f * weightKg) + (6.25f * heightCm) - (5.0f * ageYears) - 161.0f
         }
     }
 
@@ -488,13 +497,18 @@ class DatabaseRepository(
         return bmr * activityFactor
     }
 
+
     private fun processFatCaliperCalculation(
         caliper1Cm: Float?,
         caliper2Cm: Float?,
         caliper3Cm: Float?,
-        user: User
+        ageYears: Int,
+        gender: GenderType
     ): Float? {
-        LogManager.v(CALC_PROCESS_TAG, "Processing Fat Caliper: c1=$caliper1Cm cm, c2=$caliper2Cm cm, c3=$caliper3Cm cm for user ${user.id}")
+        LogManager.v(
+            CALC_PROCESS_TAG,
+            "Processing Fat Caliper: c1=$caliper1Cm cm, c2=$caliper2Cm cm, c3=$caliper3Cm cm, age=$ageYears, gender=$gender"
+        )
 
         if (caliper1Cm == null || caliper1Cm <= 0f ||
             caliper2Cm == null || caliper2Cm <= 0f ||
@@ -504,18 +518,16 @@ class DatabaseRepository(
             return null
         }
 
-        val gender = user.gender
-        val ageYears = CalculationUtil.dateToAge(user.birthDate)
-
         if (ageYears <= 0) {
-            LogManager.w(CALC_PROCESS_TAG, "Fat Caliper calculation skipped: Invalid gender ($gender) or age ($ageYears years). User ID: ${user.id}")
+            LogManager.w(CALC_PROCESS_TAG, "Fat Caliper calculation skipped: Invalid age ($ageYears).")
             return null
         }
-        LogManager.v(CALC_PROCESS_TAG, "Calculated age for Fat Caliper: $ageYears years")
 
+        // Sum of skinfolds in millimeters
         val sumSkinfoldsMm = (caliper1Cm + caliper2Cm + caliper3Cm) * 10.0f
         LogManager.v(CALC_PROCESS_TAG, "Sum of skinfolds (S): $sumSkinfoldsMm mm")
 
+        // Choose constants based on gender
         val k0: Float
         val k1: Float
         val k2: Float
@@ -536,21 +548,20 @@ class DatabaseRepository(
             }
         }
 
-        val bodyDensity = k0 - (k1 * sumSkinfoldsMm) + (k2 * sumSkinfoldsMm * sumSkinfoldsMm) - (ka * ageYears)
+        val bodyDensity =
+            k0 - (k1 * sumSkinfoldsMm) + (k2 * sumSkinfoldsMm * sumSkinfoldsMm) - (ka * ageYears)
         LogManager.v(CALC_PROCESS_TAG, "Calculated Body Density (BD): $bodyDensity")
 
         if (bodyDensity <= 0f) {
-            LogManager.w(CALC_PROCESS_TAG, "Invalid Body Density calculated: $bodyDensity. Caliper values might be outside the formula's valid range. User ID: ${user.id}")
+            LogManager.w(CALC_PROCESS_TAG, "Invalid Body Density calculated: $bodyDensity.")
             return null
         }
 
         val fatPercentage = (4.95f / bodyDensity - 4.5f) * 100.0f
         LogManager.v(CALC_PROCESS_TAG, "Calculated Fat Percentage from BD: $fatPercentage %")
 
-        return if (fatPercentage in 1.0f..70.0f) {
-            fatPercentage
-        } else {
-            LogManager.w(CALC_PROCESS_TAG, "Calculated Fat Percentage ($fatPercentage%) is outside the expected physiological range (1-70%). User ID: ${user.id}")
+        return fatPercentage.takeIf { it in 1.0f..70.0f } ?: run {
+            LogManager.w(CALC_PROCESS_TAG, "Calculated Fat Percentage ($fatPercentage%) is outside the expected physiological range (1–70%).")
             fatPercentage
         }
     }

android_app/app/src/main/java/com/health/openscale/core/eval/MeasurementEvaluator.kt

@@ -0,0 +1,145 @@
+/*
+ * openScale
+ * Copyright (C) 2025 olie.xdev <olie.xdeveloper@googlemail.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.health.openscale.core.eval
+
+import com.health.openscale.core.data.EvaluationState
+import com.health.openscale.core.data.GenderType
+import com.health.openscale.core.data.MeasurementTypeKey
+import com.health.openscale.core.utils.CalculationUtil
+import com.health.openscale.ui.screen.UserEvaluationContext
+
+data class MeasurementEvaluationResult(
+    val value: Float,
+    val lowLimit: Float,
+    val highLimit: Float,
+    val state: EvaluationState
+)
+
+/**
+ * High-level evaluation API for measurements.
+ * Delegates to MeasurementReferenceTable strategies.
+ */
+object MeasurementEvaluator {
+
+    /**
+     * Central entry point for evaluation in UI.
+     *
+     * @param typeKey           The measurement type key.
+     * @param value             The numeric value to evaluate.
+     * @param userEvaluationContext   User context (gender, height, birthDate).
+     * @param measuredAtMillis  Timestamp of the measurement (for age-on calculation).
+     *
+     * @return MeasurementEvaluationResult or null if type is not supported.
+     */
+    fun evaluate(
+        typeKey: MeasurementTypeKey,
+        value: Float,
+        userEvaluationContext: UserEvaluationContext,
+        measuredAtMillis: Long
+    ): MeasurementEvaluationResult? {
+        if (!value.isFinite()) return null
+
+        val ageYears = CalculationUtil.ageOn(
+            measuredAtMillis,
+            userEvaluationContext.birthDateMillis
+        )
+
+        return when (typeKey) {
+            MeasurementTypeKey.BODY_FAT -> evalBodyFat(value, ageYears, userEvaluationContext.gender)
+            MeasurementTypeKey.WATER    -> evalWater(value, ageYears, userEvaluationContext.gender)
+            MeasurementTypeKey.MUSCLE   -> evalMuscle(value, ageYears, userEvaluationContext.gender)
+            MeasurementTypeKey.LBM      -> evalLBM(value, ageYears, userEvaluationContext.gender)
+
+            MeasurementTypeKey.BMI      -> evalBmi(value, ageYears, userEvaluationContext.gender)
+            MeasurementTypeKey.WHTR     -> evalWHtR(value, ageYears)
+            MeasurementTypeKey.WHR      -> evalWHR(value, ageYears, userEvaluationContext.gender)
+            MeasurementTypeKey.VISCERAL_FAT -> evalVisceralFat(value, ageYears)
+
+            MeasurementTypeKey.WAIST    -> evalWaistCm(value, ageYears, userEvaluationContext.gender)
+            MeasurementTypeKey.WEIGHT   -> evalWeightAgainstTargetRange(
+                weightKg = value,
+                age = ageYears,
+                heightCm = userEvaluationContext.heightCm.toInt(),
+                gender = userEvaluationContext.gender
+            )
+
+            else -> null
+        }
+    }
+    // --- Body composition ---
+
+    fun evalBodyFat(value: Float, age: Int, gender: GenderType): MeasurementEvaluationResult =
+        when (gender) {
+            GenderType.MALE   -> MeasurementReferenceTable.fatMale.evaluate(value, age)
+            GenderType.FEMALE -> MeasurementReferenceTable.fatFemale.evaluate(value, age)
+        }
+
+    fun evalWater(value: Float, age: Int, gender: GenderType): MeasurementEvaluationResult =
+        when (gender) {
+            GenderType.MALE   -> MeasurementReferenceTable.waterMale.evaluate(value, age)
+            GenderType.FEMALE -> MeasurementReferenceTable.waterFemale.evaluate(value, age)
+        }
+
+    fun evalMuscle(value: Float, age: Int, gender: GenderType): MeasurementEvaluationResult =
+        when (gender) {
+            GenderType.MALE   -> MeasurementReferenceTable.muscleMale.evaluate(value, age)
+            GenderType.FEMALE -> MeasurementReferenceTable.muscleFemale.evaluate(value, age)
+        }
+
+    fun evalLBM(value: Float, age: Int, gender: GenderType): MeasurementEvaluationResult =
+        when (gender) {
+            GenderType.MALE   -> MeasurementReferenceTable.lbmMale.evaluate(value, age)
+            GenderType.FEMALE -> MeasurementReferenceTable.lbmFemale.evaluate(value, age)
+        }
+
+    // --- Indices ---
+
+    fun evalBmi(value: Float, age: Int, gender: GenderType): MeasurementEvaluationResult =
+        when (gender) {
+            GenderType.MALE   -> MeasurementReferenceTable.bmiMale.evaluate(value, age)
+            GenderType.FEMALE -> MeasurementReferenceTable.bmiFemale.evaluate(value, age)
+        }
+
+    fun evalWHtR(value: Float, age: Int): MeasurementEvaluationResult =
+        MeasurementReferenceTable.whtr.evaluate(value, age)
+
+    fun evalWHR(value: Float, age: Int, gender: GenderType): MeasurementEvaluationResult =
+        when (gender) {
+            GenderType.MALE   -> MeasurementReferenceTable.whrMale.evaluate(value, age)
+            GenderType.FEMALE -> MeasurementReferenceTable.whrFemale.evaluate(value, age)
+        }
+
+    fun evalVisceralFat(value: Float, age: Int): MeasurementEvaluationResult =
+        MeasurementReferenceTable.visceralFat.evaluate(value, age)
+
+    // --- Circumference / targets ---
+
+    fun evalWaistCm(value: Float, age: Int, gender: GenderType): MeasurementEvaluationResult =
+        MeasurementReferenceTable.waistStrategyCm(gender).evaluate(value, age)
+
+    /** Evaluates current weight against BMI-derived target range for given height/gender. */
+    fun evalWeightAgainstTargetRange(
+        weightKg: Float,
+        age: Int,
+        heightCm: Int,
+        gender: GenderType
+    ): MeasurementEvaluationResult =
+        MeasurementReferenceTable
+            .targetWeightStrategy(heightCm, gender)
+            .evaluate(weightKg, age)
+}

android_app/app/src/main/java/com/health/openscale/core/eval/MeasurementReferenceTable.kt

@@ -0,0 +1,213 @@
+/*
+ * openScale
+ * Copyright (C) 2025 olie.xdev <olie.xdeveloper@googlemail.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.health.openscale.core.eval
+
+import com.health.openscale.core.data.EvaluationState
+import com.health.openscale.core.data.GenderType
+
+/**
+ * Reference tables and strategies used to evaluate measurements.
+ * Uses existing MeasurementEvaluationResult (in this package) and EvaluationState (in core.data).
+ */
+object MeasurementReferenceTable {
+
+    // ----- Public strategy types -----
+
+    /** Contract for evaluating a value against reference bounds. */
+    interface EvaluationStrategy {
+        fun evaluate(value: Float, age: Int): MeasurementEvaluationResult
+    }
+
+    /** Age-specific reference range. */
+    data class AgeBand(
+        val ageMin: Int,
+        val ageMax: Int,
+        val low: Float,
+        val high: Float
+    )
+
+    /** Strategy selecting bounds by age band. */
+    class AgeBandStrategy(private val bands: List<AgeBand>) : EvaluationStrategy {
+        override fun evaluate(value: Float, age: Int): MeasurementEvaluationResult {
+            val band = bands.firstOrNull { age in it.ageMin..it.ageMax }
+                ?: return MeasurementEvaluationResult(value, -1f, -1f, EvaluationState.UNDEFINED)
+
+            val state = when {
+                value < band.low  -> EvaluationState.LOW
+                value > band.high -> EvaluationState.HIGH
+                else              -> EvaluationState.NORMAL
+            }
+            return MeasurementEvaluationResult(value, band.low, band.high, state)
+        }
+    }
+
+    /** Strategy computing bounds via formulas. */
+    class FormulaStrategy(
+        private val low: () -> Float,
+        private val high: () -> Float
+    ) : EvaluationStrategy {
+        override fun evaluate(value: Float, age: Int): MeasurementEvaluationResult {
+            val lo = low()
+            val hi = high()
+            val state = when {
+                value < lo -> EvaluationState.LOW
+                value > hi -> EvaluationState.HIGH
+                else       -> EvaluationState.NORMAL
+            }
+            return MeasurementEvaluationResult(value, lo, hi, state)
+        }
+    }
+
+    // ----- Reference tables (static) -----
+
+    // Body Fat %
+    val fatMale = AgeBandStrategy(
+        listOf(
+            AgeBand(10, 14, 11f, 16f),
+            AgeBand(15, 19, 12f, 17f),
+            AgeBand(20, 29, 13f, 18f),
+            AgeBand(30, 39, 14f, 19f),
+            AgeBand(40, 49, 15f, 20f),
+            AgeBand(50, 59, 16f, 21f),
+            AgeBand(60, 69, 17f, 22f),
+            AgeBand(70, 1000, 18f, 23f),
+        )
+    )
+    val fatFemale = AgeBandStrategy(
+        listOf(
+            AgeBand(10, 14, 16f, 21f),
+            AgeBand(15, 19, 17f, 22f),
+            AgeBand(20, 29, 18f, 23f),
+            AgeBand(30, 39, 19f, 24f),
+            AgeBand(40, 49, 20f, 25f),
+            AgeBand(50, 59, 21f, 26f),
+            AgeBand(60, 69, 22f, 27f),
+            AgeBand(70, 1000, 23f, 28f),
+        )
+    )
+
+    // Body Water %
+    val waterMale   = AgeBandStrategy(listOf(AgeBand(10, 1000, 50f, 65f)))
+    val waterFemale = AgeBandStrategy(listOf(AgeBand(10, 1000, 45f, 60f)))
+
+    // Muscle Mass %
+    val muscleMale = AgeBandStrategy(
+        listOf(
+            AgeBand(18, 29, 37.9f, 46.7f),
+            AgeBand(30, 39, 34.1f, 44.1f),
+            AgeBand(40, 49, 33.1f, 41.1f),
+            AgeBand(50, 59, 31.7f, 38.5f),
+            AgeBand(60, 69, 29.9f, 37.7f),
+            AgeBand(70, 1000, 28.7f, 43.3f),
+        )
+    )
+    val muscleFemale = AgeBandStrategy(
+        listOf(
+            AgeBand(18, 29, 28.4f, 39.8f),
+            AgeBand(30, 39, 25.0f, 36.2f),
+            AgeBand(40, 49, 24.2f, 34.2f),
+            AgeBand(50, 59, 24.7f, 33.5f),
+            AgeBand(60, 69, 22.7f, 31.9f),
+            AgeBand(70, 1000, 25.5f, 34.9f),
+        )
+    )
+
+    // BMI
+    val bmiMale = AgeBandStrategy(
+        listOf(
+            AgeBand(16, 24, 20f, 25f),
+            AgeBand(25, 34, 21f, 26f),
+            AgeBand(35, 44, 22f, 27f),
+            AgeBand(45, 54, 23f, 28f),
+            AgeBand(55, 64, 24f, 29f),
+            AgeBand(65, 90, 25f, 30f),
+        )
+    )
+    val bmiFemale = AgeBandStrategy(
+        listOf(
+            AgeBand(16, 24, 19f, 24f),
+            AgeBand(25, 34, 20f, 25f),
+            AgeBand(35, 44, 21f, 26f),
+            AgeBand(45, 54, 22f, 27f),
+            AgeBand(55, 64, 23f, 28f),
+            AgeBand(65, 90, 24f, 29f),
+        )
+    )
+
+    // WHtR
+    val whtr = AgeBandStrategy(
+        listOf(
+            AgeBand(15, 40, 0.4f, 0.5f),
+            AgeBand(41, 42, 0.4f, 0.51f),
+            AgeBand(43, 44, 0.4f, 0.53f),
+            AgeBand(45, 46, 0.4f, 0.55f),
+            AgeBand(47, 48, 0.4f, 0.57f),
+            AgeBand(49, 50, 0.4f, 0.59f),
+            AgeBand(51, 90, 0.4f, 0.6f),
+        )
+    )
+
+    // WHR
+    val whrMale   = AgeBandStrategy(listOf(AgeBand(18, 90, 0.8f, 0.9f)))
+    val whrFemale = AgeBandStrategy(listOf(AgeBand(18, 90, 0.7f, 0.8f)))
+
+    // Visceral Fat (index)
+    val visceralFat = AgeBandStrategy(listOf(AgeBand(18, 90, -1f, 12f)))
+
+    // Lean Body Mass (kg) – Italian reference P25–P75 (DOI: 10.26355/eurrev_201811_16415)
+    val lbmMale = AgeBandStrategy(
+        listOf(
+            AgeBand(18, 24, 52.90f, 62.70f),
+            AgeBand(25, 34, 53.10f, 64.80f),
+            AgeBand(35, 44, 53.83f, 65.60f),
+            AgeBand(45, 54, 53.60f, 65.20f),
+            AgeBand(55, 64, 51.63f, 61.10f),
+            AgeBand(65, 74, 48.48f, 58.20f),
+            AgeBand(75, 88, 43.35f, 60.23f),
+        )
+    )
+    val lbmFemale = AgeBandStrategy(
+        listOf(
+            AgeBand(18, 24, 34.30f, 41.90f),
+            AgeBand(25, 34, 35.20f, 43.70f),
+            AgeBand(35, 44, 35.60f, 47.10f),
+            AgeBand(45, 54, 36.10f, 44.90f),
+            AgeBand(55, 64, 35.15f, 43.95f),
+            AgeBand(65, 74, 34.10f, 42.05f),
+            AgeBand(75, 88, 33.80f, 40.40f),
+        )
+    )
+
+    // ----- Dynamic strategies -----
+
+    /** Waist circumference (cm) thresholds by gender. */
+    fun waistStrategyCm(gender: GenderType): EvaluationStrategy = when (gender) {
+        GenderType.MALE   -> AgeBandStrategy(listOf(AgeBand(18, 90, -1f, 94f)))
+        GenderType.FEMALE -> AgeBandStrategy(listOf(AgeBand(18, 90, -1f, 80f)))
+    }
+
+    /** Target weight bounds computed from height (cm) and BMI ranges by gender. */
+    fun targetWeightStrategy(heightCm: Int, gender: GenderType): EvaluationStrategy {
+        val h2 = (heightCm / 100f) * (heightCm / 100f)
+        val (bmiLo, bmiHi) = if (gender == GenderType.MALE) 20f to 25f else 19f to 24f
+        return FormulaStrategy(
+            low  = { h2 * bmiLo },
+            high = { h2 * bmiHi }
+        )
+    }
+}

android_app/app/src/main/java/com/health/openscale/core/utils/Utils.kt

@@ -30,14 +30,10 @@ import java.time.ZoneId
 import java.util.Locale
 
 object CalculationUtil {
-    fun dateToAge(birthDateMillis: Long): Int {
-        val birthDate = Instant.ofEpochMilli(birthDateMillis)
-            .atZone(ZoneId.systemDefault())
-            .toLocalDate()
-
-        val today = LocalDate.now()
-
-        return Period.between(birthDate, today).years
+    fun ageOn(dateMillis: Long, birthDateMillis: Long): Int {
+        val birth = Instant.ofEpochMilli(birthDateMillis).atZone(ZoneId.systemDefault()).toLocalDate()
+        val onDate = Instant.ofEpochMilli(dateMillis).atZone(ZoneId.systemDefault()).toLocalDate()
+        return Period.between(birth, onDate).years.coerceAtLeast(0)
     }
 
     /**

android_app/app/src/main/java/com/health/openscale/ui/screen/SharedViewModel.kt

@@ -20,24 +20,16 @@ package com.health.openscale.ui.screen
 import android.app.Application
 import android.content.ComponentName
 import android.content.Intent
-import android.util.Log
 import androidx.annotation.StringRes
-import androidx.compose.animation.core.copy
-import androidx.compose.foundation.gestures.forEach
-import androidx.compose.foundation.layout.size
 import androidx.compose.material3.SnackbarDuration
 import androidx.compose.runtime.Composable
-import androidx.compose.ui.geometry.isEmpty
 import androidx.compose.ui.graphics.vector.ImageVector
-import androidx.compose.ui.input.key.type
 import androidx.core.content.ContextCompat
-import androidx.core.graphics.values
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.ViewModelProvider
-import androidx.lifecycle.application
 import androidx.lifecycle.viewModelScope
 import com.health.openscale.R
-import com.health.openscale.core.bluetooth.data.ScaleMeasurement
+import com.health.openscale.core.data.GenderType
 import com.health.openscale.core.data.InputFieldType
 import com.health.openscale.core.data.Measurement
 import com.health.openscale.core.data.MeasurementType
@@ -131,6 +123,12 @@ data class EnrichedMeasurement(
     val valuesWithTrend: List<ValueWithDifference>
 )
 
+data class UserEvaluationContext(
+    val gender: GenderType,
+    val heightCm: Float,
+    val birthDateMillis: Long
+)
+
 /**
  * Shared ViewModel for managing UI state and business logic accessible across multiple screens.
  * It handles user selection, measurement data (CRUD operations, display, enrichment),
@@ -304,6 +302,17 @@ class SharedViewModel(
         LogManager.d(TAG, "Current measurement ID set to: $measurementId (UI/Navigation Action)")
     }
 
+    val userEvaluationContext: StateFlow<UserEvaluationContext?> =
+        selectedUser.map { u ->
+            u?.let {
+                UserEvaluationContext(
+                    gender = if (it.gender.isMale()) GenderType.MALE else GenderType.FEMALE,
+                    heightCm = it.heightCm,
+                    birthDateMillis = it.birthDate
+                )
+            }
+        }.stateIn(viewModelScope, SharingStarted.WhileSubscribed(5000L), null)
+
     // --- Measurement CRUD Operations ---
 
     fun saveMeasurement(measurementToSave: Measurement, valuesToSave: List<MeasurementValue>) {

android_app/app/src/main/java/com/health/openscale/ui/screen/components/LinearGauge.kt

@@ -0,0 +1,214 @@
+/*
+ * openScale
+ * Copyright (C) 2025 olie.xdev <olie.xdeveloper@googlemail.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.health.openscale.ui.components
+
+import androidx.compose.foundation.Canvas
+import androidx.compose.foundation.layout.*
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.geometry.Size
+import androidx.compose.ui.platform.LocalDensity
+import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.unit.dp
+import androidx.constraintlayout.compose.ConstraintLayout
+import androidx.constraintlayout.compose.ConstraintLayoutBaseScope
+import androidx.constraintlayout.compose.Dimension
+import com.health.openscale.core.data.EvaluationState
+import kotlin.math.max
+import kotlin.math.ceil
+
+@Composable
+fun LinearGauge(
+    value: Float,
+    lowLimit: Float?,
+    highLimit: Float,
+    modifier: Modifier = Modifier
+        .fillMaxWidth()
+        .height(110.dp), // a bit taller: top labels + bar + bottom label
+    labelProvider: (Float) -> String = { "%.1f".format(it) }
+) {
+    val barHeight = 10f
+    val EPS = 1e-3f
+
+    val lowColor    = EvaluationState.LOW.toColor()
+    val normalColor = EvaluationState.NORMAL.toColor()
+    val highColor   = EvaluationState.HIGH.toColor()
+    val indicatorColor = MaterialTheme.colorScheme.onSurface
+    val guideColor     = MaterialTheme.colorScheme.onSurface.copy(alpha = 0.25f)
+
+    val hasFirst = lowLimit != null
+    val lo = lowLimit
+    var hi = highLimit
+    if (hasFirst && lo!! > hi) hi = lo
+
+    var span = if (hasFirst) (hi - lo!!) / 2f else 0.3f * hi
+    val margin = 0.05f * span
+    span = when {
+        hasFirst && value - margin < lo!! - span -> lo - value + margin
+        !hasFirst && value - margin < hi - span  -> hi - value + margin
+        value + margin > hi + span               -> value - hi + margin
+        else                                     -> span
+    }
+    span = when {
+        span <= 1f   -> ceil(span * 10.0) / 10.0
+        span <= 10f  -> ceil(span.toDouble())
+        else         -> 5.0 * ceil(span / 5.0)
+    }.toFloat().let { if (it <= EPS) 1f else it }
+
+    val minV = if (lo == null && value >= 0f && hi >= 0f) 0f
+    else ((lo ?: hi) - span).coerceAtLeast(0f)
+    val maxV = (hi + span).let { if (it <= minV + EPS) minV + 1f else it }
+    val denom = (maxV - minV).let { if (it <= EPS) 1f else it }
+
+    fun frac(v: Float) = ((v - minV) / denom).coerceIn(0f, 1f)
+    fun map(v: Float, w: Float) = frac(v) * w
+
+    val fMin  = 0f
+    val fLow  = if (hasFirst) frac(lo!!) else null
+    val fHigh = frac(hi)
+    val fMax  = 1f
+    val fVal  = frac(value) // current value position (for bottom label)
+
+    Column(modifier = modifier) {
+
+        // ----- Top labels -----
+        ConstraintLayout(
+            Modifier
+                .fillMaxWidth()
+                .height(14.dp)
+                .padding(horizontal = 4.dp)
+        ) {
+            val gMin  = createGuidelineFromAbsoluteLeft(fraction = fMin)
+            val gLow  = fLow?.let { createGuidelineFromAbsoluteLeft(fraction = it) }
+            val gHigh = createGuidelineFromAbsoluteLeft(fraction = fHigh)
+            val gMax  = createGuidelineFromAbsoluteLeft(fraction = fMax)
+
+            val style = MaterialTheme.typography.labelSmall
+
+            @Composable
+            fun Label(text: String, guide: ConstraintLayoutBaseScope.VerticalAnchor) {
+                val ref = createRef()
+                Text(
+                    text = text,
+                    style = style,
+                    maxLines = 1,
+                    modifier = Modifier.constrainAs(ref) {
+                        width = Dimension.wrapContent
+                        start.linkTo(guide)
+                        end.linkTo(guide)
+                        bottom.linkTo(parent.bottom) // closer to bar
+                    },
+                    textAlign = TextAlign.Center
+                )
+            }
+
+            Label(labelProvider(minV), gMin)
+            if (hasFirst) Label(labelProvider(lo!!), gLow!!)
+            Label(labelProvider(hi), gHigh)
+            Label(labelProvider(maxV), gMax)
+        }
+
+        // ----- Bar + guides + indicator -----
+        Box(Modifier.fillMaxWidth().height(42.dp)) {
+            val density = LocalDensity.current
+            Canvas(Modifier.fillMaxSize()) {
+                val w = size.width
+                val yTop = (size.height - barHeight) / 2f
+
+                val xLow = if (hasFirst) map(lo, w) else 0f
+                val xHigh = map(hi, w)
+                val xVal  = map(value, w)
+
+                if (hasFirst) {
+                    drawRect(
+                        color = lowColor,
+                        topLeft = Offset(0f, yTop),
+                        size = Size(max(0f, xLow), barHeight)
+                    )
+                }
+                drawRect(
+                    color = normalColor,
+                    topLeft = Offset(xLow, yTop),
+                    size = Size(max(0f, xHigh - xLow), barHeight)
+                )
+                drawRect(
+                    color = highColor,
+                    topLeft = Offset(xHigh, yTop),
+                    size = Size(max(0f, w - xHigh), barHeight)
+                )
+
+                val extraPx   = with(density) { 10.dp.toPx() }
+                val tickStroke = with(density) { 1.dp.toPx() }
+
+                fun drawGuide(x: Float) {
+                    drawLine(
+                        color = guideColor,
+                        start = Offset(x, yTop - extraPx),
+                        end   = Offset(x, yTop + barHeight + extraPx),
+                        strokeWidth = tickStroke
+                    )
+                }
+
+                drawGuide(0f)
+                if (hasFirst) drawGuide(xLow)
+                drawGuide(xHigh)
+                drawGuide(w)
+
+                // Bigger indicator triangle
+                val triH = 26f
+                val triW = 24f
+                drawPath(
+                    path = androidx.compose.ui.graphics.Path().apply {
+                        moveTo(xVal, yTop + barHeight)
+                        lineTo(xVal - triW / 2f, yTop + barHeight + triH)
+                        lineTo(xVal + triW / 2f, yTop + barHeight + triH)
+                        close()
+                    },
+                    color = indicatorColor
+                )
+            }
+        }
+
+        // ----- Current value label centered under marker -----
+        ConstraintLayout(
+            Modifier
+                .fillMaxWidth()
+                .height(20.dp)
+                .padding(horizontal = 4.dp)
+        ) {
+            val gVal = createGuidelineFromAbsoluteLeft(fraction = fVal)
+            val style = MaterialTheme.typography.labelMedium
+            val ref = createRef()
+
+            Text(
+                text = labelProvider(value),
+                style = style,
+                modifier = Modifier.constrainAs(ref) {
+                    width = Dimension.wrapContent
+                    start.linkTo(gVal)
+                    end.linkTo(gVal) // horizontally center to marker
+                    top.linkTo(parent.top)
+                },
+                textAlign = TextAlign.Center
+            )
+        }
+    }
+}

android_app/app/src/main/java/com/health/openscale/ui/screen/graph/GraphScreen.kt

@@ -17,14 +17,12 @@
  */
 package com.health.openscale.ui.screen.graph
 
-import android.content.Context
 import androidx.compose.foundation.layout.*
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Close
 import androidx.compose.material.icons.filled.Edit
 import androidx.compose.material3.*
 import androidx.compose.material3.ExperimentalMaterial3Api
-import androidx.compose.material3.SheetValue
 import androidx.compose.material3.ModalBottomSheet
 import androidx.compose.material3.rememberModalBottomSheetState
 import androidx.compose.runtime.*
@@ -38,7 +36,6 @@ import androidx.navigation.NavController
 import com.health.openscale.R
 import com.health.openscale.core.data.Trend
 import com.health.openscale.core.database.UserPreferenceKeys
-import com.health.openscale.core.model.MeasurementWithValues
 import com.health.openscale.ui.navigation.Routes
 import com.health.openscale.ui.screen.SharedViewModel
 import com.health.openscale.ui.screen.ValueWithDifference
@@ -46,9 +43,6 @@ import com.health.openscale.ui.screen.components.LineChart
 import com.health.openscale.ui.screen.components.provideFilterTopBarAction
 import com.health.openscale.ui.screen.overview.MeasurementValueRow
 import java.text.DateFormat
-import java.text.SimpleDateFormat
-import java.time.Instant
-import java.time.ZoneId
 import java.util.Date
 import java.util.Locale
 
@@ -62,6 +56,7 @@ fun GraphScreen(
     val isLoading by sharedViewModel.isBaseDataLoading.collectAsState()
     val allMeasurementsWithValues by sharedViewModel.allMeasurementsForSelectedUser.collectAsState()
     val selectedUserId by sharedViewModel.selectedUserId.collectAsState()
+    val userEvalContext by sharedViewModel.userEvaluationContext.collectAsState()
 
     val sheetState = rememberModalBottomSheetState(skipPartiallyExpanded = false)
     var sheetMeasurementId by rememberSaveable { mutableStateOf<Int?>(null) }
@@ -180,11 +175,13 @@ fun GraphScreen(
 
                 visibleValues.forEach { v ->
                     MeasurementValueRow(
-                        ValueWithDifference(
+                        valueWithTrend = ValueWithDifference(
                             currentValue = v,
                             difference = null,
                             trend = Trend.NOT_APPLICABLE
-                        )
+                        ),
+                        userEvaluationContext = userEvalContext,
+                        measuredAtMillis = mwv.measurement.timestamp
                     )
                 }
             }

android_app/app/src/main/java/com/health/openscale/ui/screen/overview/OverviewScreen.kt

@@ -17,17 +17,16 @@
  */
 package com.health.openscale.ui.screen.overview
 
-import android.R.attr.targetId
 import android.content.Context
 import android.widget.Toast
 import androidx.compose.animation.AnimatedVisibility
-import androidx.compose.animation.animateColorAsState
-import androidx.compose.animation.core.tween
 import androidx.compose.foundation.BorderStroke
 import androidx.compose.foundation.background
+import androidx.compose.foundation.clickable
 import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Box
 import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.IntrinsicSize
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxSize
@@ -39,7 +38,6 @@ import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.itemsIndexed
 import androidx.compose.foundation.lazy.rememberLazyListState
-import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.filled.BluetoothSearching
 import androidx.compose.material.icons.filled.Add
@@ -56,7 +54,6 @@ import androidx.compose.material.icons.filled.ExpandLess
 import androidx.compose.material.icons.filled.ExpandMore
 import androidx.compose.material.icons.filled.PersonAdd
 import androidx.compose.material.icons.filled.PersonSearch
-import androidx.compose.material.icons.filled.QuestionMark
 import androidx.compose.material3.Button
 import androidx.compose.material3.ButtonDefaults
 import androidx.compose.material3.Card
@@ -75,6 +72,7 @@ import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateListOf
+import androidx.compose.runtime.mutableStateMapOf
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberCoroutineScope
@@ -85,19 +83,24 @@ import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.platform.LocalContext
-import androidx.compose.ui.res.painterResource
 import androidx.compose.ui.res.stringResource
 import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.dp
 import androidx.navigation.NavController
 import com.health.openscale.R
+import com.health.openscale.core.data.EvaluationState
 import com.health.openscale.core.data.InputFieldType
+import com.health.openscale.core.data.MeasurementTypeKey
 import com.health.openscale.core.data.Trend
 import com.health.openscale.core.model.MeasurementWithValues
 import com.health.openscale.core.database.UserPreferenceKeys
+import com.health.openscale.core.eval.MeasurementEvaluator
+import com.health.openscale.ui.components.LinearGauge
 import com.health.openscale.ui.components.RoundMeasurementIcon
 import com.health.openscale.ui.navigation.Routes
 import com.health.openscale.ui.screen.SharedViewModel
+import com.health.openscale.ui.screen.UserEvaluationContext
 import com.health.openscale.ui.screen.ValueWithDifference
 import com.health.openscale.ui.screen.bluetooth.BluetoothViewModel
 import com.health.openscale.ui.screen.bluetooth.ConnectionStatus
@@ -105,9 +108,8 @@ import com.health.openscale.ui.screen.components.LineChart
 import com.health.openscale.ui.screen.components.provideFilterTopBarAction
 import kotlinx.coroutines.delay
 import kotlinx.coroutines.launch
+import java.text.DateFormat
 import java.text.SimpleDateFormat
-import java.time.Instant
-import java.time.ZoneId
 import java.util.Date
 import java.util.Locale
 
@@ -316,6 +318,9 @@ fun OverviewScreen(
                     (type.inputType == InputFieldType.FLOAT || type.inputType == InputFieldType.INT) // Ensure it's a plottable type
         }
     }
+
+    val userEvalContext by sharedViewModel.userEvaluationContext.collectAsState()
+
     // --- End of reverted chart selection logic ---
 
     val savedDeviceAddress by bluetoothViewModel.savedScaleAddress.collectAsState()
@@ -463,7 +468,8 @@ fun OverviewScreen(
                             MeasurementCard(
                                 measurementWithValues = enrichedItem.measurementWithValues,
                                 processedValuesForDisplay = enrichedItem.valuesWithTrend,
-                                onEdit = {
+                                userEvaluationContext = userEvalContext,
+                                        onEdit = {
                                     navController.navigate(
                                         Routes.measurementDetail(
                                             enrichedItem.measurementWithValues.measurement.id,
@@ -628,6 +634,7 @@ fun NoMeasurementsCard(navController: NavController, selectedUserId: Int?) {
 fun MeasurementCard(
     measurementWithValues: MeasurementWithValues,
     processedValuesForDisplay: List<ValueWithDifference>,
+    userEvaluationContext: UserEvaluationContext?,
     onEdit: () -> Unit,
     onDelete: () -> Unit,
     isHighlighted: Boolean = false
@@ -635,6 +642,9 @@ fun MeasurementCard(
     val highlightColor = MaterialTheme.colorScheme.primary.copy(alpha = 0.12f)
     val highlightBorder = BorderStroke(1.dp, MaterialTheme.colorScheme.primary)
 
+    val measuredAtMillis = measurementWithValues.measurement.timestamp
+    val expandedTypeIds = remember { mutableStateMapOf<Int, Boolean>() }
+
     val dateFormatted = remember(measurementWithValues.measurement.timestamp) {
         SimpleDateFormat("E, dd.MM.yyyy HH:mm", Locale.getDefault())
             .format(Date(measurementWithValues.measurement.timestamp))
@@ -653,8 +663,6 @@ fun MeasurementCard(
     val allActiveProcessedValues = remember(processedValuesForDisplay) {
         processedValuesForDisplay.filter { it.currentValue.type.isEnabled }
     }
-
-
     Card(
         modifier = Modifier.fillMaxWidth(),
         border = if (isHighlighted) highlightBorder else null,
@@ -679,19 +687,26 @@ fun MeasurementCard(
                     modifier = Modifier.weight(1f) // Date takes available space
                 )
                 val iconButtonSize = 36.dp // Standard size for action icons
-                val actionIconColor = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.8f)
+                val actionIconColor =
+                    MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.8f)
 
                 IconButton(onClick = onEdit, modifier = Modifier.size(iconButtonSize)) {
                     Icon(
                         Icons.Default.Edit,
-                        contentDescription = stringResource(R.string.action_edit_measurement_desc, dateFormatted),
+                        contentDescription = stringResource(
+                            R.string.action_edit_measurement_desc,
+                            dateFormatted
+                        ),
                         tint = actionIconColor
                     )
                 }
                 IconButton(onClick = onDelete, modifier = Modifier.size(iconButtonSize)) {
                     Icon(
                         Icons.Default.Delete,
-                        contentDescription = stringResource(R.string.action_delete_measurement_desc, dateFormatted),
+                        contentDescription = stringResource(
+                            R.string.action_delete_measurement_desc,
+                            dateFormatted
+                        ),
                         tint = actionIconColor
                     )
                 }
@@ -699,7 +714,10 @@ fun MeasurementCard(
                 // Conditional expand/collapse icon button for non-pinned values,
                 // only shown if there are non-pinned values and no pinned values (to avoid duplicate expand button logic)
                 if (nonPinnedValues.isNotEmpty() && pinnedValues.isEmpty()) {
-                    IconButton(onClick = { isExpanded = !isExpanded }, modifier = Modifier.size(iconButtonSize)) {
+                    IconButton(
+                        onClick = { isExpanded = !isExpanded },
+                        modifier = Modifier.size(iconButtonSize)
+                    ) {
                         Icon(
                             imageVector = if (isExpanded) Icons.Filled.ExpandLess else Icons.Filled.ExpandMore,
                             contentDescription = stringResource(if (isExpanded) R.string.action_show_less_desc else R.string.action_show_more_desc)
@@ -717,41 +735,51 @@ fun MeasurementCard(
                 )
             ) {
                 if (pinnedValues.isNotEmpty()) {
-                    Column(verticalArrangement = Arrangement.spacedBy(10.dp)) {
+                    Column(verticalArrangement = Arrangement.spacedBy(0.dp)) {
                         pinnedValues.forEach { valueWithTrend ->
-                            MeasurementValueRow(valueWithTrend)
+                            MeasurementRowExpandable(
+                                valueWithTrend = valueWithTrend,
+                                userEvaluationContext = userEvaluationContext,
+                                measuredAtMillis = measuredAtMillis,
+                                expandedTypeIds = expandedTypeIds
+                            )
                         }
                     }
                 }
             }
 
+
             // Animated section for non-pinned measurement values (collapsible)
             if (nonPinnedValues.isNotEmpty()) {
                 AnimatedVisibility(visible = isExpanded || pinnedValues.isEmpty()) { // Also visible if no pinned values and not expanded (default state)
                     Column(
-                        modifier = Modifier.padding(
-                            start = 16.dp, end = 16.dp,
-                            top = if (pinnedValues.isNotEmpty()) 12.dp else 8.dp, // Smaller top padding if no pinned values
-                            bottom = 8.dp
-                        ),
-                        verticalArrangement = Arrangement.spacedBy(10.dp)
+                        modifier = Modifier.padding(start = 16.dp, end = 16.dp, top = 0.dp, bottom = 0.dp),
+                        verticalArrangement = Arrangement.spacedBy(0.dp)
                     ) {
                         nonPinnedValues.forEach { valueWithTrend ->
-                            MeasurementValueRow(valueWithTrend)
+                            MeasurementRowExpandable(
+                                valueWithTrend = valueWithTrend,
+                                userEvaluationContext = userEvaluationContext,
+                                measuredAtMillis = measuredAtMillis,
+                                expandedTypeIds = expandedTypeIds
+                            )
                         }
                     }
                 }
             }
 
+
             // Footer: Expand/Collapse TextButton (only if there are non-pinned values and also pinned values,
             // or if there are non-pinned values and it's not the default expanded state for only non-pinned).
-            if (nonPinnedValues.isNotEmpty() && (pinnedValues.isNotEmpty() || !isExpanded) ) {
+            if (nonPinnedValues.isNotEmpty() && (pinnedValues.isNotEmpty() || !isExpanded)) {
                 // Show divider if the expandable section is visible or if pinned items are present (button will always be there)
                 if (isExpanded || pinnedValues.isNotEmpty()) {
-                    HorizontalDivider(modifier = Modifier.padding(
-                        top = if (isExpanded && nonPinnedValues.isNotEmpty()) 4.dp else if (pinnedValues.isNotEmpty()) 8.dp else 0.dp,
-                        bottom = 0.dp
-                    ))
+                    HorizontalDivider(
+                        modifier = Modifier.padding(
+                            top = if (isExpanded && nonPinnedValues.isNotEmpty()) 4.dp else if (pinnedValues.isNotEmpty()) 8.dp else 0.dp,
+                            bottom = 0.dp
+                        )
+                    )
                 }
 
                 TextButton(
@@ -790,69 +818,141 @@ fun MeasurementCard(
 }
 
 /**
- * A row Composable that displays a single measurement value, including its type icon,
- * name, value, unit, and trend indicator if applicable.
+ * Displays one measurement row: icon + name + (optional) trend on the left,
+ * value and an evaluation symbol on the right.
  *
- * @param valueWithTrend The [ValueWithDifference] object containing the current value,
- *                       type information, difference from a previous value, and trend.
+ * Symbol rules:
+ *  - ▲ / ▼ / ●: based on the evaluation state (HIGH / LOW / NORMAL/UNDEFINED)
+ *  - ! (error color): shown if there is no matching age band at measurement time
+ *    OR if a percentage value is outside a plausible range (0–100%).
+ *
+ * Note:
+ *  - Non-numeric types (TEXT/DATE/TIME) are not evaluated (show ● if not flagged).
  */
 @Composable
-fun MeasurementValueRow(valueWithTrend: ValueWithDifference) {
+fun MeasurementValueRow(
+    valueWithTrend: ValueWithDifference,
+    userEvaluationContext: UserEvaluationContext?,
+    measuredAtMillis: Long
+) {
     val type = valueWithTrend.currentValue.type
-    val originalValue = valueWithTrend.currentValue.value // This is Measurement.Value object
+    val originalValue = valueWithTrend.currentValue.value
     val difference = valueWithTrend.difference
     val trend = valueWithTrend.trend
+    val unitName = type.unit.displayName
 
+    // Localized display value for each input type
     val displayValue = when (type.inputType) {
         InputFieldType.FLOAT -> originalValue.floatValue?.let { "%.1f".format(Locale.getDefault(), it) }
-        InputFieldType.INT -> originalValue.intValue?.toString()
-        InputFieldType.TEXT -> originalValue.textValue
-        InputFieldType.DATE -> originalValue.dateValue?.let {
-            SimpleDateFormat("dd.MM.yyyy", Locale.getDefault()).format(Date(it))
+        InputFieldType.INT   -> originalValue.intValue?.toString()
+        InputFieldType.TEXT  -> originalValue.textValue
+        InputFieldType.DATE  -> originalValue.dateValue?.let {
+            DateFormat.getDateInstance(DateFormat.SHORT, Locale.getDefault()).format(Date(it))
         }
-        InputFieldType.TIME -> originalValue.dateValue?.let {
-            SimpleDateFormat("HH:mm", Locale.getDefault()).format(Date(it))
+        InputFieldType.TIME  -> originalValue.dateValue?.let {
+            DateFormat.getTimeInstance(DateFormat.SHORT, Locale.getDefault()).format(Date(it))
         }
-    } ?: "-" // Default to dash if value is null
+    } ?: "-"
 
     val context = LocalContext.current
-    val iconMeasurementType = remember(type.icon) {type.icon }
+    val iconMeasurementType = remember(type.icon) { type.icon }
+
+    // Extract numeric value only for evaluable numeric types
+    val numeric: Float? = when (type.inputType) {
+        InputFieldType.FLOAT -> originalValue.floatValue
+        InputFieldType.INT   -> originalValue.intValue?.toFloat()
+        else                 -> null
+    }
+
+    // Compute evaluation if possible
+    val evalResult = remember(valueWithTrend, userEvaluationContext, measuredAtMillis) {
+        if (userEvaluationContext != null && numeric != null) {
+            MeasurementEvaluator.evaluate(
+                typeKey = type.key,
+                value = numeric,
+                userEvaluationContext = userEvaluationContext,
+                measuredAtMillis = measuredAtMillis
+            )
+        } else null
+    }
+
+    // Flag 1: no matching age band (limits are negative)
+    val noAgeBand: Boolean = evalResult?.let { it.lowLimit < 0f || it.highLimit < 0f } ?: false
+
+    // Flag 2: percent outside a plausible range (0..100)
+    val plausible = plausiblePercentRangeFor(type.key)
+    val outOfPlausibleRange =
+        if (numeric == null) {
+            false
+        } else {
+            plausible?.let { numeric < it.start || numeric > it.endInclusive }
+                ?: (unitName == "%" && (numeric < 0f || numeric > 100f)) // Fallback
+        }
+
+    val flagged = noAgeBand || outOfPlausibleRange
+
+    // Base evaluation state (falls back to UNDEFINED when not evaluable)
+    val evalState = evalResult?.state ?: EvaluationState.UNDEFINED
+
+    // Symbol selection
+    val evalSymbol = if (flagged) {
+        "!"
+    } else {
+        when (evalState) {
+            EvaluationState.LOW       -> "▼"
+            EvaluationState.NORMAL    -> "●"
+            EvaluationState.HIGH      -> "▲"
+            EvaluationState.UNDEFINED -> "●"
+        }
+    }
+
+    // Symbol color: error for "!", otherwise mapped from eval state
+    val evalColor = if (flagged) {
+        MaterialTheme.colorScheme.error
+    } else {
+        evalState.toColor()
+    }
 
     Row(
-        modifier = Modifier.fillMaxWidth(),
+        modifier = Modifier
+            .fillMaxWidth()
+            .height(IntrinsicSize.Min)
+            .padding(vertical = 6.dp),
         verticalAlignment = Alignment.CenterVertically
     ) {
-        // Left part: Icon and Type Name
+        // Left side: icon + labels
         Row(
-            modifier = Modifier.weight(1f), // Takes available space, pushing value & trend to the right
+            modifier = Modifier.weight(1f),
             verticalAlignment = Alignment.CenterVertically
         ) {
             RoundMeasurementIcon(
                 icon = iconMeasurementType,
-                backgroundTint = Color(type.color),
+                backgroundTint = Color(type.color)
             )
             Spacer(modifier = Modifier.width(12.dp))
             Column(verticalArrangement = Arrangement.Center) {
                 Text(
                     text = type.getDisplayName(context),
                     style = MaterialTheme.typography.titleSmall,
-                    maxLines = 1,
+                    maxLines = 1
                 )
+
+                // Show trend only for numeric types with a difference
                 if (difference != null && trend != Trend.NOT_APPLICABLE) {
                     Spacer(modifier = Modifier.height(1.dp))
                     Row(verticalAlignment = Alignment.CenterVertically) {
                         val trendIconVector = when (trend) {
-                            Trend.UP -> Icons.Filled.ArrowUpward
+                            Trend.UP   -> Icons.Filled.ArrowUpward
                             Trend.DOWN -> Icons.Filled.ArrowDownward
                             Trend.NONE -> null
-                            else -> null
+                            else       -> null
                         }
-                        val subtleGrayColor = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.7f)
+                        val subtle = MaterialTheme.colorScheme.onSurfaceVariant.copy(alpha = 0.7f)
                         if (trendIconVector != null) {
                             Icon(
                                 imageVector = trendIconVector,
                                 contentDescription = trend.name,
-                                tint = subtleGrayColor,
+                                tint = subtle,
                                 modifier = Modifier.size(12.dp)
                             )
                             Spacer(modifier = Modifier.width(3.dp))
@@ -861,23 +961,218 @@ fun MeasurementValueRow(valueWithTrend: ValueWithDifference) {
                             text = (if (difference > 0 && trend != Trend.NONE) "+" else "") +
                                     when (type.inputType) {
                                         InputFieldType.FLOAT -> "%.1f".format(Locale.getDefault(), difference)
-                                        InputFieldType.INT -> difference.toInt().toString()
-                                        else -> ""
-                                    } + " ${type.unit.displayName}",
+                                        InputFieldType.INT   -> difference.toInt().toString()
+                                        else                 -> ""
+                                    } + " $unitName",
                             style = MaterialTheme.typography.bodySmall,
-                            color = subtleGrayColor
+                            color = subtle
                         )
                     }
                 } else if (type.inputType == InputFieldType.FLOAT || type.inputType == InputFieldType.INT) {
+                    // Keep vertical spacing consistent when no trend is shown
                     Spacer(modifier = Modifier.height((MaterialTheme.typography.bodySmall.fontSize.value + 2).dp))
                 }
             }
         }
-        Text(
-            text = "$displayValue ${type.unit.displayName}",
-            style = MaterialTheme.typography.bodyLarge,
-            textAlign = TextAlign.End,
+
+        // Right side: value + evaluation symbol
+        Row(
+            verticalAlignment = Alignment.CenterVertically,
             modifier = Modifier.padding(start = 8.dp)
-        )
+        ) {
+            Text(
+                text = "$displayValue $unitName",
+                style = MaterialTheme.typography.bodyLarge,
+                textAlign = TextAlign.End
+            )
+            Spacer(Modifier.width(6.dp))
+            Text(
+                text = evalSymbol,
+                color = evalColor,
+                style = MaterialTheme.typography.bodyLarge
+            )
+        }
     }
 }
+
+
+/**
+ * Small, prominent banner for evaluation problems (e.g., no age band or implausible value).
+ *
+ * @param message Localized message to display inside the banner.
+ */
+@Composable
+private fun EvaluationErrorBanner(message: String) {
+    Box(
+        modifier = Modifier
+            .fillMaxWidth()
+            .padding(8.dp)
+            .clip(MaterialTheme.shapes.medium)
+            .background(MaterialTheme.colorScheme.errorContainer)
+            .padding(12.dp)
+    ) {
+        Row(verticalAlignment = Alignment.CenterVertically) {
+            Icon(
+                imageVector = Icons.Filled.Error,
+                contentDescription = null,
+                tint = MaterialTheme.colorScheme.onErrorContainer
+            )
+            Spacer(Modifier.width(8.dp))
+            Text(
+                text = message,
+                color = MaterialTheme.colorScheme.onErrorContainer,
+                style = MaterialTheme.typography.bodyMedium
+            )
+        }
+    }
+}
+
+
+/**
+ * Returns a broad **plausible** percentage range for selected measurement types.
+ *
+ * This is **not** a clinical reference band. It’s only used to catch obviously
+ * incorrect values (e.g., sensor glitches, unit mix-ups) before attempting
+ * a proper evaluation. The ranges are intentionally wide.
+ *
+ * @param typeKey The measurement type to check.
+ * @return A closed percent range [min .. max] if the metric is percentage-based and supported,
+ *         or `null` if no generic plausibility range is defined for this type.
+ */
+private fun plausiblePercentRangeFor(typeKey: MeasurementTypeKey): ClosedFloatingPointRange<Float>? =
+    when (typeKey) {
+        MeasurementTypeKey.WATER      -> 35f..75f
+        MeasurementTypeKey.BODY_FAT   -> 3f..70f
+        MeasurementTypeKey.MUSCLE     -> 15f..60f
+        else -> null
+    }
+
+
+/**
+ * One measurement row that can expand to show a gauge or an info banner.
+ *
+ * Behavior:
+ * - If a normal evaluation is possible, the row expands to a LinearGauge.
+ * - If no age band exists or the value is outside a plausible range, the row expands to an info banner.
+ * - The clickable state of the row follows the above rules (only clickable when there is something meaningful to show).
+ *
+ * @param valueWithTrend The value and meta info for this row.
+ * @param userEvaluationContext The context needed to evaluate the value (gender, age, etc.); can be null.
+ * @param measuredAtMillis Timestamp of the measurement (used by the evaluator).
+ * @param expandedTypeIds State map holding expand/collapse flags per measurement type id.
+ * @param modifier Optional modifier for the container column.
+ * @param gaugeHeightDp Height of the gauge when shown.
+ */
+@Composable
+fun MeasurementRowExpandable(
+    valueWithTrend: ValueWithDifference,
+    userEvaluationContext: UserEvaluationContext?,
+    measuredAtMillis: Long,
+    expandedTypeIds: MutableMap<Int, Boolean>,
+    modifier: Modifier = Modifier,
+    gaugeHeightDp: Dp = 80.dp,
+) {
+    val type = valueWithTrend.currentValue.type
+
+    // Extract numeric value for evaluation / plausibility checks
+    val numeric: Float? = when (type.inputType) {
+        InputFieldType.FLOAT -> valueWithTrend.currentValue.value.floatValue
+        InputFieldType.INT   -> valueWithTrend.currentValue.value.intValue?.toFloat()
+        else                 -> null
+    }
+
+    // Run evaluation (or keep null when not possible)
+    val evalResult = remember(valueWithTrend, userEvaluationContext, measuredAtMillis) {
+        if (userEvaluationContext == null || numeric == null) {
+            null
+        } else {
+            MeasurementEvaluator.evaluate(
+                typeKey = type.key,
+                value = numeric,
+                userEvaluationContext = userEvaluationContext,
+                measuredAtMillis = measuredAtMillis
+            )
+        }
+    }
+
+    // Special cases:
+    // 1) No age band available -> evaluator returns negative limits
+    val noAgeBand = evalResult?.let { it.lowLimit < 0f || it.highLimit < 0f } ?: false
+
+    // 2) Implausible value for percentage-based metrics
+    val unitName = type.unit.displayName
+    val plausible = plausiblePercentRangeFor(type.key)
+    val outOfPlausibleRange =
+        if (numeric == null) {
+            false
+        } else {
+            plausible?.let { numeric < it.start || numeric > it.endInclusive }
+                ?: (unitName == "%" && (numeric < 0f || numeric > 100f))
+        }
+
+    // Expand is allowed when:
+    // - a normal evaluation exists (valid limits), OR
+    // - we have one of the special cases (to show the info banner)
+    val canExpand = (evalResult != null && !noAgeBand) || noAgeBand || outOfPlausibleRange
+
+    Column(modifier) {
+        // The main row – clickable only when `canExpand` is true.
+        Box(
+            modifier = Modifier
+                .fillMaxWidth()
+                .clickable(enabled = canExpand) {
+                    val cur = expandedTypeIds[type.id] ?: false
+                    expandedTypeIds[type.id] = !cur
+                }
+        ) {
+            // Uses your existing row (with ●/▲/▼ or ! logic inside).
+            MeasurementValueRow(
+                valueWithTrend = valueWithTrend,
+                userEvaluationContext = userEvaluationContext,
+                measuredAtMillis = measuredAtMillis
+            )
+        }
+
+        val unit = type.unit.displayName
+
+        // Expanded content:
+        AnimatedVisibility(visible = canExpand && (expandedTypeIds[type.id] == true)) {
+            when {
+                noAgeBand -> {
+                    EvaluationErrorBanner(
+                        message = stringResource(R.string.eval_no_age_band)
+                    )
+                }
+                outOfPlausibleRange -> {
+                    val plausible = plausiblePercentRangeFor(type.key) ?: (0f..100f)
+                    EvaluationErrorBanner(
+                        message = stringResource(
+                            R.string.eval_out_of_plausible_range_percent,
+                            plausible.start,
+                            plausible.endInclusive
+                        )
+                    )
+                }
+                // Normal evaluation → show gauge
+                evalResult != null -> {
+                    Column(
+                        Modifier.padding(start = 16.dp, end = 16.dp, top = 6.dp, bottom = 2.dp)
+                    ) {
+                        LinearGauge(
+                            value = evalResult.value,
+                            lowLimit = if (evalResult.lowLimit < 0f) null else evalResult.lowLimit,
+                            highLimit = evalResult.highLimit,
+                            modifier = Modifier
+                                .fillMaxWidth()
+                                .height(gaugeHeightDp),
+                            labelProvider = { v ->
+                                String.format(Locale.getDefault(), "%,.1f %s", v, unit)
+                            }
+                        )
+                    }
+                }
+            }
+        }
+    }
+}
+

android_app/app/src/main/java/com/health/openscale/ui/screen/settings/UserSettingsScreen.kt

@@ -92,7 +92,7 @@ fun UserSettingsScreen(
         items(users) { user ->
             // Calculate age. This will be recalculated if user.birthDate changes.
             val age = remember(user.birthDate) {
-                CalculationUtil.dateToAge(user.birthDate)
+                CalculationUtil.ageOn(System.currentTimeMillis(), user.birthDate)
             }
 
             ListItem(

android_app/app/src/main/res/values-de/strings.xml

@@ -434,6 +434,10 @@
     <string name="delete_db_successful">Gesamte Datenbank wurde gelöscht.</string>
     <string name="delete_db_error">Fehler beim Löschen der gesamten Datenbank.</string>
 
+    <!-- Evaluation Nachrichten -->
+    <string name="eval_no_age_band">Keine Bewertung möglich: Kein passender Altersbereich zum Messzeitpunkt.</string>
+    <string name="eval_out_of_plausible_range_percent">Auffälliger Wert: außerhalb des plausiblen Bereichs (%1$.0f–%2$.0f%%).</string>
+
     <!-- BluetoothViewModel Snackbar Messages -->
     <string name="bt_snackbar_permissions_required_to_scan">Bluetooth-Berechtigungen werden zum Scannen von Geräten benötigt.</string>
     <string name="bt_snackbar_bluetooth_disabled_to_scan">Bluetooth ist deaktiviert. Bitte aktiviere es, um nach Geräten zu scannen.</string>

android_app/app/src/main/res/values/strings.xml

@@ -436,6 +436,10 @@
     <string name="delete_db_successful">Entire database has been deleted.</string>
     <string name="delete_db_error">Error deleting entire database.</string>
 
+    <!-- Evaluation Messages -->
+    <string name="eval_no_age_band">No evaluation possible: No matching age band at the time of measurement.</string>
+    <string name="eval_out_of_plausible_range_percent">Unusual value: outside the plausible range (%1$.0f–%2$.0f%%).</string>
+
     <!-- BluetoothViewModel Snackbar Messages -->
     <string name="bt_snackbar_permissions_required_to_scan">Bluetooth permissions are required to scan for devices.</string>
     <string name="bt_snackbar_bluetooth_disabled_to_scan">Bluetooth is disabled. Please enable it to scan for devices.</string>

android_app/gradle/libs.versions.toml

@@ -17,6 +17,7 @@ documentfile = "1.1.0"
 composeCharts = "2.1.3"
 composeReorderable = "2.5.1"
 compose-material = "1.7.8"
+constraintlayout-compose = "1.1.1"
 kotlinCsv = "1.10.0"
 blessedKotlin = "3.0.9"
 blessedJava = "2.5.2"
@@ -38,6 +39,7 @@ androidx-ui-test-manifest = { group = "androidx.compose.ui", name = "ui-test-man
 androidx-ui-test-junit4 = { group = "androidx.compose.ui", name = "ui-test-junit4" }
 androidx-navigation-compose = { group = "androidx.navigation", name = "navigation-compose", version.ref = "navigation" }
 androidx-material3 = { group = "androidx.compose.material3", name = "material3" }
+androidx-constraintlayout-compose = { group = "androidx.constraintlayout", name = "constraintlayout-compose", version.ref = "constraintlayout-compose" }
 androidx-room-runtime = { module = "androidx.room:room-runtime", version.ref = "room" }
 androidx-room-ktx = { module = "androidx.room:room-ktx", version.ref = "room" }
 androidx-room-compiler = { module = "androidx.room:room-compiler", version.ref = "room" }