diff --git a/app/src/main/java/de/luh/hci/mi/vibrationpattern/MainActivity.kt b/app/src/main/java/de/luh/hci/mi/vibrationpattern/MainActivity.kt
index 6343c0e..13073dd 100644
--- a/app/src/main/java/de/luh/hci/mi/vibrationpattern/MainActivity.kt
+++ b/app/src/main/java/de/luh/hci/mi/vibrationpattern/MainActivity.kt
@@ -5,29 +5,30 @@ import android.os.VibrationEffect
 import android.os.Vibrator
 import androidx.activity.ComponentActivity
 import androidx.activity.compose.setContent
-import androidx.compose.foundation.layout.Arrangement
 import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.Spacer
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.height
-import androidx.compose.material.Button
-import androidx.compose.material.ButtonDefaults
+import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.selection.selectable
+import androidx.compose.foundation.selection.selectableGroup
 import androidx.compose.material.MaterialTheme
+import androidx.compose.material.RadioButton
 import androidx.compose.material.Surface
 import androidx.compose.material.Text
 import androidx.compose.runtime.Composable
-import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
-import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
-import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.semantics.Role
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import de.luh.hci.mi.vibrationpattern.ui.theme.VibrationPatternTheme
+
 class MainActivity : ComponentActivity() {
     private lateinit var vibrator: Vibrator
 
@@ -35,90 +36,84 @@ class MainActivity : ComponentActivity() {
         super.onCreate(savedInstanceState)
         vibrator = getSystemService(Vibrator::class.java)
         setContent {
-            View()
+            View(vibrator.hasVibrator(), vibrator.hasAmplitudeControl())
         }
     }
 
     @Preview(showBackground = true)
     @Composable
-    fun View() {
-        var isVibrating by remember { mutableStateOf(false) }
+    fun PreviewView() {
+
+        View(hasVibrator = true, hasAmplitudeControl = true)
+    }
+
+    @Composable
+    fun View(hasVibrator: Boolean, hasAmplitudeControl: Boolean) {
 
         VibrationPatternTheme {
             Surface(
-                modifier = Modifier.fillMaxSize(),
+                modifier = Modifier
+                    .fillMaxSize()
+                    .padding(8.dp),
                 color = MaterialTheme.colors.background,
             ) {
-                Column(
-                    modifier = Modifier.fillMaxSize(),
-                    verticalArrangement = Arrangement.Center,
-                    horizontalAlignment = Alignment.CenterHorizontally
-                ) {
-                    Text(text = "Select vibration pattern")
-                    val vibrationSupport =
-                        if (vibrator.hasVibrator()) "✅ Supports vibration" else "❌ Vibration not supported"
-                    val amplitudeSupport =
-                        if (vibrator.hasAmplitudeControl()) "✅ Supports amplitude control" else "❌ Amplitude control not supported"
-                    Text(text = vibrationSupport, fontSize = 12.sp)
-                    Text(text = amplitudeSupport, fontSize = 12.sp)
-                    Spacer(modifier = Modifier.height(50.dp))
+                Column {
+                    Text(
+                        text = "Play vibration pattern",
+                        fontSize = 32.sp,
+                        color = MaterialTheme.colors.primary
+                    )
+                    Text(
+                        text = "has vibrator: $hasVibrator",
+                        fontSize = 12.sp,
+                        color = MaterialTheme.colors.secondary
+                    )
+                    Text(
+                        text = "has amplitude control: $hasAmplitudeControl",
+                        fontSize = 12.sp,
+                        color = MaterialTheme.colors.secondary
+                    )
 
+                    Spacer(modifier = Modifier.height(20.dp))
 
-                    Column(
-                        modifier = Modifier.fillMaxWidth(0.5f)
-                    ) {
-                        Button(
-                            onClick = { vibrator.vibrate(HEART); isVibrating = true },
-                            modifier = Modifier.fillMaxWidth()
-                        ) {
-                            Text("Heartbeat")
-                        }
-                        Button(
-                            onClick = { vibrator.vibrate(SOS); isVibrating = true },
-                            modifier = Modifier.fillMaxWidth()
-                        ) {
-                            Text("SOS")
-                        }
-                        Button(
-                            onClick = { vibrator.vibrate(WALTZ); isVibrating = true },
-                            modifier = Modifier.fillMaxWidth()
-                        ) {
-                            Text("Waltz")
-                        }
-
-                        Spacer(modifier = Modifier.height(20.dp))
-                        Button(
-                            onClick = { vibrator.vibrate(vibes.random()); isVibrating = true },
-                            modifier = Modifier.fillMaxWidth()
-                        ) {
-                            Text("Random")
-                        }
-                        Button(
-                            onClick = { vibrator.vibrate(ANGRY); isVibrating = true },
-                            modifier = Modifier.fillMaxWidth()
-                        ) {
-                            Text("Angry")
-                        }
-                        Button(
-                            onClick = { vibrator.vibrate(CHILL); isVibrating = true },
-                            modifier = Modifier.fillMaxWidth()
-                        ) {
-                            Text("Chill")
+                    val radioOptions =
+                        listOf("None", "Heartbeat", "SOS", "Waltz", "Angry", "Chill", "Random")
+                    val (selectedOption, onOptionSelected) = remember {
+                        mutableStateOf(radioOptions[0])
+                    }
+                    Column(Modifier.selectableGroup()) {
+                        radioOptions.forEach { text ->
+                            Row(
+                                Modifier
+                                    .fillMaxWidth()
+                                    .height(48.dp)
+                                    .padding(horizontal = 16.dp)
+                                    .selectable(
+                                        selected = (text == selectedOption),
+                                        onClick = {
+                                            onOptionSelected(text)
+                                            when (text) {
+                                                "Heartbeat" -> vibrator.vibrate(HEART)
+                                                "SOS" -> vibrator.vibrate(SOS)
+                                                "Waltz" -> vibrator.vibrate(WALTZ)
+                                                "Angry" -> vibrator.vibrate(ANGRY)
+                                                "Chill" -> vibrator.vibrate(CHILL)
+                                                "Random" -> vibrator.vibrate(vibes.random())
+                                                else -> vibrator.cancel()
+                                            }
+                                        },
+                                        role = Role.RadioButton
+                                    ),
+                                verticalAlignment = Alignment.CenterVertically
+                            ) {
+                                RadioButton(selected = (text == selectedOption), onClick = null)
+                                Text(
+                                    text = text,
+                                    modifier = Modifier.padding(start = 16.dp)
+                                )
+                            }
                         }
                     }
-
-                    Spacer(modifier = Modifier.height(50.dp))
-                    Button(
-                        enabled = isVibrating,
-                        onClick = { vibrator.cancel(); isVibrating = false },
-                        colors = ButtonDefaults.buttonColors(
-                            backgroundColor = Color.Red,
-                            contentColor = Color.White
-                        )
-                    ) {
-                        Text("Stop")
-                    }
-
                 }
             }
         }
@@ -136,10 +131,27 @@ class MainActivity : ComponentActivity() {
         )
         private val SOS = VibrationEffect.createWaveform(
             longArrayOf(
-                0, 100, 100, 100, 100, 100, 100,
-                300, 100, 300, 100, 300, 100,
-                100, 100, 100, 100, 100, 100,
-                0, 1000
+                0,
+                100,
+                100,
+                100,
+                100,
+                100,
+                100,
+                300,
+                100,
+                300,
+                100,
+                300,
+                100,
+                100,
+                100,
+                100,
+                100,
+                100,
+                100,
+                0,
+                1000
             ), 1
         )
         private val WALTZ = VibrationEffect.createWaveform(