diff --git a/.idea/misc.xml b/.idea/misc.xml
index 704c883..bdd9278 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="ExternalStorageConfigurationManager" enabled="true" />
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_17" default="true" project-jdk-name="Android Studio default JDK" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_11" default="true" project-jdk-name="Android Studio default JDK" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/build/classes" />
   </component>
   <component name="ProjectType">
diff --git a/app/src/main/java/be/ugent/sel/studeez/activities/MainActivity.kt b/app/src/main/java/be/ugent/sel/studeez/activities/MainActivity.kt
index 318fe7a..6829e7f 100644
--- a/app/src/main/java/be/ugent/sel/studeez/activities/MainActivity.kt
+++ b/app/src/main/java/be/ugent/sel/studeez/activities/MainActivity.kt
@@ -1,6 +1,7 @@
 package be.ugent.sel.studeez.activities
 
 import android.os.Bundle
+import android.util.Log
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
 import androidx.compose.foundation.layout.fillMaxSize
@@ -11,6 +12,8 @@ import androidx.compose.runtime.Composable
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.tooling.preview.Preview
 import be.ugent.sel.studeez.StudeezApp
+import be.ugent.sel.studeez.screens.session.SessionTest
+import be.ugent.sel.studeez.screens.session.test
 import be.ugent.sel.studeez.ui.theme.StudeezTheme
 import dagger.hilt.android.AndroidEntryPoint
 
@@ -30,6 +33,16 @@ class MainActivity : ComponentActivity() {
             }
         }
     }
+
+    override fun onStop() {
+        test()
+        super.onStop()
+    }
+
+    override fun onStart() {
+        SessionTest.updateTimer()
+        super.onStart()
+    }
 }
 
 @Composable
diff --git a/app/src/main/java/be/ugent/sel/studeez/data/local/models/timer_functional/FunctionalTimer.kt b/app/src/main/java/be/ugent/sel/studeez/data/local/models/timer_functional/FunctionalTimer.kt
index dae27c6..bb7423e 100644
--- a/app/src/main/java/be/ugent/sel/studeez/data/local/models/timer_functional/FunctionalTimer.kt
+++ b/app/src/main/java/be/ugent/sel/studeez/data/local/models/timer_functional/FunctionalTimer.kt
@@ -1,7 +1,7 @@
 package be.ugent.sel.studeez.data.local.models.timer_functional
 
 abstract class FunctionalTimer(initialValue: Int) {
-    val time: Time = Time(initialValue)
+    var time: Time = Time(initialValue)
     var view: StudyState = StudyState.FOCUS
 
     fun getHoursMinutesSeconds(): HoursMinutesSeconds {
diff --git a/app/src/main/java/be/ugent/sel/studeez/data/local/models/timer_functional/Time.kt b/app/src/main/java/be/ugent/sel/studeez/data/local/models/timer_functional/Time.kt
index ec7702d..83be75d 100644
--- a/app/src/main/java/be/ugent/sel/studeez/data/local/models/timer_functional/Time.kt
+++ b/app/src/main/java/be/ugent/sel/studeez/data/local/models/timer_functional/Time.kt
@@ -4,6 +4,10 @@ class Time(initialTime: Int) {
 
     var time = initialTime
 
+    fun min(i: Int) {
+        time -= i
+    }
+
     fun minOne() {
         time--
     }
diff --git a/app/src/main/java/be/ugent/sel/studeez/screens/session/SessionScreen.kt b/app/src/main/java/be/ugent/sel/studeez/screens/session/SessionScreen.kt
index 0559291..dee4f12 100644
--- a/app/src/main/java/be/ugent/sel/studeez/screens/session/SessionScreen.kt
+++ b/app/src/main/java/be/ugent/sel/studeez/screens/session/SessionScreen.kt
@@ -3,6 +3,7 @@ package be.ugent.sel.studeez.screens.session
 import android.media.MediaPlayer
 import android.media.RingtoneManager
 import android.net.Uri
+import android.util.Log
 import androidx.compose.foundation.background
 import androidx.compose.foundation.border
 import androidx.compose.foundation.layout.Box
@@ -31,10 +32,20 @@ import androidx.hilt.navigation.compose.hiltViewModel
 import be.ugent.sel.studeez.R
 import be.ugent.sel.studeez.data.local.models.timer_functional.FunctionalPomodoroTimer
 import be.ugent.sel.studeez.data.local.models.timer_functional.FunctionalTimer.StudyState
+import be.ugent.sel.studeez.data.local.models.timer_functional.Time
 import be.ugent.sel.studeez.resources
 import kotlinx.coroutines.delay
+import java.time.Duration
+import java.time.LocalDateTime
+import java.time.ZoneId
+import java.util.*
+import kotlin.properties.Delegates
+import kotlin.time.Duration.Companion.hours
+import kotlin.time.Duration.Companion.minutes
 import kotlin.time.Duration.Companion.seconds
 
+var start: LocalDateTime = Calendar.getInstance().time.toInstant().atZone(ZoneId.systemDefault()).toLocalDateTime()
+
 @Composable
 fun SessionScreen(
     open: (String) -> Unit,
@@ -46,6 +57,8 @@ fun SessionScreen(
     val mediaplayer = MediaPlayer.create(context, uri)
     mediaplayer.isLooping = false
 
+    SessionTest.setNewViewModel(viewModel = viewModel)
+
     Column(
        modifier = Modifier.padding(10.dp)
    ) {
@@ -81,6 +94,11 @@ fun SessionScreen(
     }
 }
 
+private operator fun Time.minus(time: Time): Time {
+    return Time(this.time - time.time)
+
+}
+
 @Composable
 private fun Timer(viewModel: SessionViewModel = hiltViewModel(), mediaplayer: MediaPlayer) {
     var tikker by remember { mutableStateOf(false) }
@@ -146,6 +164,33 @@ private fun Timer(viewModel: SessionViewModel = hiltViewModel(), mediaplayer: Me
             }
         }
     }
+}
+
+fun test() {
+    start = Calendar.getInstance().time.toInstant().atZone(ZoneId.systemDefault()).toLocalDateTime()
+}
+
+object SessionTest {
+    lateinit var viewModel: SessionViewModel
+    private var isSession: Boolean = false
+
+    fun setNewViewModel(viewModel: SessionViewModel) {
+        isSession = true
+        this.viewModel = viewModel
+    }
+
+    fun updateTimer() {
+        if (isSession) {
+            val end = Calendar.getInstance().time.toInstant().atZone(ZoneId.systemDefault()).toLocalDateTime()
+
+            val duration = Duration.between(start, end)
+
+            val hours = duration.toHours()
+            val minutes = duration.toMinutes() % 60
+            val seconds = duration.seconds % 60
+            viewModel.getTimer().time.min((hours + minutes + seconds).toInt())
+        }
+    }
 
 
 }
\ No newline at end of file