diff --git a/.github/workflows/gradle-wrapper-validation.yml b/.github/workflows/gradle-wrapper-validation.yml
new file mode 100644
index 0000000..405a2b3
--- /dev/null
+++ b/.github/workflows/gradle-wrapper-validation.yml
@@ -0,0 +1,10 @@
+name: "Validate Gradle Wrapper"
+on: [push, pull_request]
+
+jobs:
+  validation:
+    name: "Validation"
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: gradle/wrapper-validation-action@v1
diff --git a/README.md b/README.md
index 0f756fe..1620cc5 100644
--- a/README.md
+++ b/README.md
@@ -2,13 +2,10 @@
 
 Redirect outgoing calls to Signal/Telegram/Threema.
 
-[comment]: <> ([<img)
-
-[comment]: <> (     src="https://fdroid.gitlab.io/artwork/badge/get-it-on.png")
-
-[comment]: <> (     alt="Get it on F-Droid")
-
-[comment]: <> (     height="80">]&#40;https://f-droid.org/packages/me.lucky.red/&#41;)
+[<img
+     src="https://fdroid.gitlab.io/artwork/badge/get-it-on.png"
+     alt="Get it on F-Droid"
+     height="80">](https://f-droid.org/packages/me.lucky.red/)
 [<img
       src="https://play.google.com/intl/en_us/badges/images/generic/en-play-badge.png"
       alt="Get it on Google Play"
diff --git a/app/build.gradle b/app/build.gradle
index d2b783f..f8d6430 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -10,8 +10,8 @@ android {
         applicationId "me.lucky.red"
         minSdk 29
         targetSdk 32
-        versionCode 8
-        versionName "1.0.7"
+        versionCode 9
+        versionName "1.0.8"
 
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
@@ -39,10 +39,10 @@ android {
 }
 
 dependencies {
-    implementation 'androidx.core:core-ktx:1.7.0'
-    implementation 'androidx.appcompat:appcompat:1.4.1'
-    implementation 'com.google.android.material:material:1.5.0'
-    implementation 'androidx.constraintlayout:constraintlayout:2.1.3'
+    implementation 'androidx.core:core-ktx:1.8.0'
+    implementation 'androidx.appcompat:appcompat:1.4.2'
+    implementation 'com.google.android.material:material:1.6.1'
+    implementation 'androidx.constraintlayout:constraintlayout:2.1.4'
     testImplementation 'junit:junit:4.13.2'
     androidTestImplementation 'androidx.test.ext:junit:1.1.3'
     androidTestImplementation 'androidx.test.espresso:espresso-core:3.4.0'
diff --git a/app/src/main/java/me/lucky/red/CallRedirectionService.kt b/app/src/main/java/me/lucky/red/CallRedirectionService.kt
index 131a2be..1a0c4b7 100644
--- a/app/src/main/java/me/lucky/red/CallRedirectionService.kt
+++ b/app/src/main/java/me/lucky/red/CallRedirectionService.kt
@@ -8,6 +8,7 @@ import android.provider.ContactsContract
 import android.telecom.CallRedirectionService
 import android.telecom.PhoneAccountHandle
 import androidx.annotation.RequiresPermission
+import java.lang.ref.WeakReference
 
 class CallRedirectionService : CallRedirectionService() {
     companion object {
@@ -16,7 +17,7 @@ class CallRedirectionService : CallRedirectionService() {
         private const val TELEGRAM_MIMETYPE = "$PREFIX/vnd.org.telegram.messenger.android.call"
         private const val THREEMA_MIMETYPE = "$PREFIX/vnd.ch.threema.app.call"
         private const val WHATSAPP_MIMETYPE = "$PREFIX/vnd.com.whatsapp.voip.call"
-        private val MIMETYPES = mapOf(
+        private val MIMETYPE_TO_WEIGHT = mapOf(
             SIGNAL_MIMETYPE to 0,
             TELEGRAM_MIMETYPE to 1,
             THREEMA_MIMETYPE to 2,
@@ -25,9 +26,15 @@ class CallRedirectionService : CallRedirectionService() {
         private val FALLBACK_MIMETYPES = arrayOf(
             WHATSAPP_MIMETYPE,
         )
+        private val MIMETYPE_TO_DST_NAME = mapOf(
+            SIGNAL_MIMETYPE to R.string.destination_signal,
+            TELEGRAM_MIMETYPE to R.string.destination_telegram,
+            THREEMA_MIMETYPE to R.string.destination_threema,
+            WHATSAPP_MIMETYPE to R.string.fallback_destination_whatsapp,
+        )
     }
 
-    lateinit var prefs: Preferences
+    private lateinit var prefs: Preferences
     private lateinit var window: PopupWindow
     private var connectivityManager: ConnectivityManager? = null
 
@@ -43,7 +50,7 @@ class CallRedirectionService : CallRedirectionService() {
 
     private fun init() {
         prefs = Preferences(this)
-        window = PopupWindow(this)
+        window = PopupWindow(this, WeakReference(this))
         connectivityManager = getSystemService(ConnectivityManager::class.java)
     }
 
@@ -52,7 +59,7 @@ class CallRedirectionService : CallRedirectionService() {
         initialPhoneAccount: PhoneAccountHandle,
         allowInteractiveResponse: Boolean,
     ) {
-        if (!prefs.isServiceEnabled || !hasInternet() || !allowInteractiveResponse) {
+        if (!prefs.isEnabled || !hasInternet() || !allowInteractiveResponse) {
             placeCallUnmodified()
             return
         }
@@ -63,18 +70,12 @@ class CallRedirectionService : CallRedirectionService() {
             placeCallUnmodified()
             return
         }
-        val record = records.minByOrNull { MIMETYPES[it.mimetype] ?: 0 }
+        val record = records.minByOrNull { MIMETYPE_TO_WEIGHT[it.mimetype] ?: 0 }
         if (record == null || (record.mimetype in FALLBACK_MIMETYPES && !prefs.isFallbackChecked)) {
             placeCallUnmodified()
             return
         }
-        window.show(record.uri, when (record.mimetype) {
-            SIGNAL_MIMETYPE -> R.string.destination_signal
-            TELEGRAM_MIMETYPE -> R.string.destination_telegram
-            THREEMA_MIMETYPE -> R.string.destination_threema
-            WHATSAPP_MIMETYPE -> R.string.fallback_destination_whatsapp
-            else -> return
-        })
+        window.show(record.uri, MIMETYPE_TO_DST_NAME[record.mimetype] ?: return)
     }
 
     @RequiresPermission(Manifest.permission.READ_CONTACTS)
@@ -83,7 +84,7 @@ class CallRedirectionService : CallRedirectionService() {
         val cursor = contentResolver.query(
             Uri.withAppendedPath(
                 ContactsContract.PhoneLookup.CONTENT_FILTER_URI,
-                Uri.encode(phoneNumber)
+                Uri.encode(phoneNumber),
             ),
             arrayOf(ContactsContract.PhoneLookup._ID),
             null,
@@ -109,8 +110,8 @@ class CallRedirectionService : CallRedirectionService() {
             arrayOf(ContactsContract.Data._ID, ContactsContract.Data.MIMETYPE),
              "${ContactsContract.Data.CONTACT_ID} = ? AND " +
                      "${ContactsContract.Data.MIMETYPE} IN " +
-                     "(${MIMETYPES.keys.joinToString(",") { "?" }})",
-            arrayOf(contactId, *MIMETYPES.keys.toTypedArray()),
+                     "(${MIMETYPE_TO_WEIGHT.keys.joinToString(",") { "?" }})",
+            arrayOf(contactId, *MIMETYPE_TO_WEIGHT.keys.toTypedArray()),
             null,
         )
         cursor?.apply {
diff --git a/app/src/main/java/me/lucky/red/MainActivity.kt b/app/src/main/java/me/lucky/red/MainActivity.kt
index c9e3fd3..4861f27 100644
--- a/app/src/main/java/me/lucky/red/MainActivity.kt
+++ b/app/src/main/java/me/lucky/red/MainActivity.kt
@@ -23,6 +23,7 @@ class MainActivity : AppCompatActivity() {
 
     private lateinit var binding: ActivityMainBinding
     private lateinit var prefs: Preferences
+    private lateinit var window: PopupWindow
     private var roleManager: RoleManager? = null
 
     private val registerForCallRedirectionRole =
@@ -42,14 +43,20 @@ class MainActivity : AppCompatActivity() {
         setup()
     }
 
+    override fun onDestroy() {
+        super.onDestroy()
+        window.cancel()
+    }
+
     private fun init() {
         prefs = Preferences(this)
+        window = PopupWindow(this, null)
         roleManager = getSystemService(RoleManager::class.java)
         binding.apply {
             redirectionDelay.value = (prefs.redirectionDelay / 1000).toFloat()
             popupPosition.editText?.setText(prefs.popupPosition.toString())
             fallback.isChecked = prefs.isFallbackChecked
-            toggle.isChecked = prefs.isServiceEnabled
+            toggle.isChecked = prefs.isEnabled
         }
     }
 
@@ -61,6 +68,9 @@ class MainActivity : AppCompatActivity() {
             redirectionDelay.addOnChangeListener { _, value, _ ->
                 prefs.redirectionDelay = (value * 1000).toLong()
             }
+            popupPosition.setEndIconOnClickListener {
+                window.preview()
+            }
             popupPosition.editText?.doAfterTextChanged {
                 try {
                     prefs.popupPosition = it?.toString()?.toInt() ?: return@doAfterTextChanged
@@ -75,7 +85,7 @@ class MainActivity : AppCompatActivity() {
                     requestPermissions()
                     return@setOnCheckedChangeListener
                 }
-                prefs.isServiceEnabled = isChecked
+                prefs.isEnabled = isChecked
             }
         }
     }
diff --git a/app/src/main/java/me/lucky/red/PopupWindow.kt b/app/src/main/java/me/lucky/red/PopupWindow.kt
index 7bfafe0..9476c39 100644
--- a/app/src/main/java/me/lucky/red/PopupWindow.kt
+++ b/app/src/main/java/me/lucky/red/PopupWindow.kt
@@ -1,6 +1,7 @@
 package me.lucky.red
 
 import android.Manifest
+import android.content.Context
 import android.content.Intent
 import android.graphics.PixelFormat
 import android.media.AudioManager
@@ -10,20 +11,19 @@ import android.view.LayoutInflater
 import android.view.WindowManager
 import android.widget.TextView
 import androidx.annotation.RequiresPermission
+import java.lang.ref.WeakReference
 import java.util.*
 import kotlin.concurrent.timerTask
 
-class PopupWindow(private val service: CallRedirectionService) {
-    private val windowManager = service
-        .applicationContext
-        .getSystemService(WindowManager::class.java)
-    private val audioManager = service
-        .applicationContext
-        .getSystemService(AudioManager::class.java)
+class PopupWindow(
+    private val ctx: Context,
+    private val service: WeakReference<CallRedirectionService>?,
+) {
+    private val prefs = Preferences(ctx)
+    private val windowManager = ctx.getSystemService(WindowManager::class.java)
+    private val audioManager = ctx.getSystemService(AudioManager::class.java)
     @Suppress("InflateParams")
-    private val view = LayoutInflater
-        .from(service.applicationContext)
-        .inflate(R.layout.popup, null)
+    private val view = LayoutInflater.from(ctx).inflate(R.layout.popup, null)
     private val layoutParams = WindowManager.LayoutParams().apply {
         format = PixelFormat.TRANSLUCENT
         flags = WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
@@ -31,18 +31,32 @@ class PopupWindow(private val service: CallRedirectionService) {
         gravity = Gravity.BOTTOM
         width = WindowManager.LayoutParams.WRAP_CONTENT
         height = WindowManager.LayoutParams.WRAP_CONTENT
-        y = service.prefs.popupPosition
+        y = prefs.popupPosition
     }
     private var timer: Timer? = null
 
     init {
         view.setOnClickListener {
             cancel()
-            service.placeCallUnmodified()
+            service?.get()?.placeCallUnmodified()
         }
     }
 
+    fun preview() {
+        remove()
+        layoutParams.y = prefs.popupPosition
+        val destinations = mutableListOf(
+            R.string.destination_signal,
+            R.string.destination_telegram,
+            R.string.destination_threema,
+        )
+        if (prefs.isFallbackChecked) destinations.add(R.string.fallback_destination_whatsapp)
+        setDescription(destinations.random())
+        add()
+    }
+
     fun show(uri: Uri, destinationId: Int) {
+        val service = service?.get() ?: return
         if (!remove()) {
             service.placeCallUnmodified()
             return
@@ -65,23 +79,27 @@ class PopupWindow(private val service: CallRedirectionService) {
                 return@timerTask
             }
             service.cancelCall()
-        }, service.prefs.redirectionDelay)
-        view.findViewById<TextView>(R.id.description).text = String.format(
-            service.getString(R.string.popup),
-            service.getString(destinationId),
-        )
+        }, prefs.redirectionDelay)
+        setDescription(destinationId)
         if (!add()) {
             timer?.cancel()
             service.placeCallUnmodified()
         }
     }
 
+    private fun setDescription(id: Int) {
+        view.findViewById<TextView>(R.id.description).text = ctx.getString(
+            R.string.popup,
+            ctx.getString(id),
+        )
+    }
+
     @RequiresPermission(Manifest.permission.CALL_PHONE)
     private fun call(data: Uri) {
         Intent(Intent.ACTION_VIEW).let {
             it.data = data
             it.flags = Intent.FLAG_ACTIVITY_NEW_TASK
-            service.startActivity(it)
+            ctx.startActivity(it)
         }
     }
 
diff --git a/app/src/main/java/me/lucky/red/Preferences.kt b/app/src/main/java/me/lucky/red/Preferences.kt
index 33b11b1..7948d8a 100644
--- a/app/src/main/java/me/lucky/red/Preferences.kt
+++ b/app/src/main/java/me/lucky/red/Preferences.kt
@@ -6,20 +6,23 @@ import androidx.preference.PreferenceManager
 
 class Preferences(ctx: Context) {
     companion object {
-        private const val SERVICE_ENABLED = "service_enabled"
+        private const val ENABLED = "enabled"
         private const val REDIRECTION_DELAY = "redirection_delay"
         private const val POPUP_POSITION = "popup_position_y"
         private const val FALLBACK_CHECKED = "fallback_checked"
 
         private const val DEFAULT_REDIRECTION_DELAY = 2000L
         private const val DEFAULT_POPUP_POSITION = 333
+
+        // migration
+        private const val SERVICE_ENABLED = "service_enabled"
     }
 
     private val prefs = PreferenceManager.getDefaultSharedPreferences(ctx)
 
-    var isServiceEnabled: Boolean
-        get() = prefs.getBoolean(SERVICE_ENABLED, false)
-        set(value) = prefs.edit { putBoolean(SERVICE_ENABLED, value) }
+    var isEnabled: Boolean
+        get() = prefs.getBoolean(ENABLED, prefs.getBoolean(SERVICE_ENABLED, false))
+        set(value) = prefs.edit { putBoolean(ENABLED, value) }
 
     var redirectionDelay: Long
         get() = prefs.getLong(REDIRECTION_DELAY, DEFAULT_REDIRECTION_DELAY)
diff --git a/app/src/main/res/drawable/ic_baseline_check_circle_24.xml b/app/src/main/res/drawable/ic_baseline_check_circle_24.xml
new file mode 100644
index 0000000..5e111ca
--- /dev/null
+++ b/app/src/main/res/drawable/ic_baseline_check_circle_24.xml
@@ -0,0 +1,10 @@
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportWidth="24"
+    android:viewportHeight="24"
+    android:tint="?attr/colorControlNormal">
+  <path
+      android:fillColor="@android:color/white"
+      android:pathData="M12,2C6.48,2 2,6.48 2,12s4.48,10 10,10 10,-4.48 10,-10S17.52,2 12,2zM10,17l-5,-5 1.41,-1.41L10,14.17l7.59,-7.59L19,8l-9,9z"/>
+</vector>
diff --git a/app/src/main/res/layout/activity_main.xml b/app/src/main/res/layout/activity_main.xml
index 3753d2f..97ae04d 100644
--- a/app/src/main/res/layout/activity_main.xml
+++ b/app/src/main/res/layout/activity_main.xml
@@ -55,6 +55,8 @@
 
             <com.google.android.material.textfield.TextInputLayout
                 android:id="@+id/popupPosition"
+                app:endIconMode="custom"
+                app:endIconDrawable="@drawable/ic_baseline_check_circle_24"
                 android:hint="@string/popup_position"
                 android:layout_width="match_parent"
                 android:layout_height="wrap_content">
diff --git a/app/src/main/res/values-fr/string.xml b/app/src/main/res/values-fr/strings.xml
similarity index 100%
rename from app/src/main/res/values-fr/string.xml
rename to app/src/main/res/values-fr/strings.xml
diff --git a/app/src/main/res/values/strings.xml b/app/src/main/res/values/strings.xml
index 88442f2..dd378e5 100644
--- a/app/src/main/res/values/strings.xml
+++ b/app/src/main/res/values/strings.xml
@@ -6,7 +6,7 @@
     <string name="destination_signal">Signal</string>
     <string name="destination_telegram">Telegram</string>
     <string name="destination_threema">Threema</string>
-    <string name="redirection_delay_description">Delay before a call will be redirected.</string>
+    <string name="redirection_delay_description">The delay before a call will be redirected.</string>
     <string name="popup_position">Popup position</string>
     <string name="fallback">Fallback</string>
     <string name="fallback_description">Redirect to WhatsApp if no other available.</string>
diff --git a/build.gradle b/build.gradle
index 9262dea..9d1ce67 100644
--- a/build.gradle
+++ b/build.gradle
@@ -5,8 +5,8 @@ buildscript {
         mavenCentral()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:7.1.1'
-        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.6.10"
+        classpath 'com.android.tools.build:gradle:7.2.1'
+        classpath "org.jetbrains.kotlin:kotlin-gradle-plugin:1.7.0"
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
diff --git a/fastlane/metadata/android/en-US/changelogs/9.txt b/fastlane/metadata/android/en-US/changelogs/9.txt
new file mode 100644
index 0000000..135fd01
--- /dev/null
+++ b/fastlane/metadata/android/en-US/changelogs/9.txt
@@ -0,0 +1 @@
+popup window preview
diff --git a/fastlane/metadata/android/en-US/images/phoneScreenshots/1.png b/fastlane/metadata/android/en-US/images/phoneScreenshots/1.png
index 1c4e57e..8b9cbff 100644
Binary files a/fastlane/metadata/android/en-US/images/phoneScreenshots/1.png and b/fastlane/metadata/android/en-US/images/phoneScreenshots/1.png differ
diff --git a/fastlane/metadata/android/ru-RU/full_description.txt b/fastlane/metadata/android/ru-RU/full_description.txt
index 3004d7f..933fa76 100644
--- a/fastlane/metadata/android/ru-RU/full_description.txt
+++ b/fastlane/metadata/android/ru-RU/full_description.txt
@@ -1,4 +1,4 @@
-Минимальное приложение для перенаправления исходящих вызовов в Signal/Telegram/Threema.
+Мини приложение для перенаправления исходящих вызовов в Signal/Telegram/Threema.
 
 Вы можете отменить перенаправление, кликнув на всплывающее сообщение "Перенаправление в..".
 
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index a2e01c0..4a48a57 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -1,6 +1,6 @@
+#Tue Jun 14 23:11:06 MSK 2022
 distributionBase=GRADLE_USER_HOME
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.3.3-bin.zip
 distributionPath=wrapper/dists
-distributionSha256Sum=f581709a9c35e9cb92e16f585d2c4bc99b2b1a5f85d2badbd3dc6bff59e1e6dd
-distributionUrl=https\://services.gradle.org/distributions/gradle-7.2-bin.zip
-zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME