feat(billing): implement a simple RevenueCat billing system

Only for the Google Play version. The FOSS version remains free.

app/build.gradle.kts

@@ -116,7 +116,8 @@ dependencies {
     implementation(libs.androidx.room.ktx)
     ksp(libs.androidx.room.compiler)
 
-    "playImplementation"(libs.purchases)
+    "playImplementation"(libs.revenuecat.purchases)
+    "playImplementation"(libs.revenuecat.purchases.ui)
 
     testImplementation(libs.junit)
 

app/src/foss/java/org/nsh07/pomodoro/billing/FossBillingManager.kt

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2025 Nishant Mishra
+ *
+ * This file is part of Tomato - a minimalist pomodoro timer for Android.
+ *
+ * Tomato 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.
+ *
+ * Tomato 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 Tomato.
+ * If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package org.nsh07.pomodoro.billing
+
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
+
+/**
+ * Google Play implementation of BillingManager
+ */
+class FossBillingManager : BillingManager {
+    override val isPlus = MutableStateFlow(true).asStateFlow()
+}
+
+object BillingManagerProvider {
+    val manager: BillingManager = FossBillingManager()
+}

app/src/foss/java/org/nsh07/pomodoro/billing/TomatoPlusPaywallDialog.kt

@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) 2025 Nishant Mishra
+ *
+ * This file is part of Tomato - a minimalist pomodoro timer for Android.
+ *
+ * Tomato 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.
+ *
+ * Tomato 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 Tomato.
+ * If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package org.nsh07.pomodoro.billing
+
+import androidx.compose.runtime.Composable
+
+@Composable
+fun TomatoPlusPaywallDialog(
+    isPlus: Boolean,
+    onDismiss: () -> Unit
+) {
+}

app/src/foss/java/org/nsh07/pomodoro/billing/initializePurchases.kt

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2025 Nishant Mishra
+ *
+ * This file is part of Tomato - a minimalist pomodoro timer for Android.
+ *
+ * Tomato 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.
+ *
+ * Tomato 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 Tomato.
+ * If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package org.nsh07.pomodoro.billing
+
+import android.content.Context
+
+fun initializePurchases(context: Context) {}

app/src/main/java/org/nsh07/pomodoro/MainActivity.kt

@@ -30,12 +30,10 @@ import androidx.lifecycle.compose.collectAsStateWithLifecycle
 import org.nsh07.pomodoro.ui.AppScreen
 import org.nsh07.pomodoro.ui.settingsScreen.viewModel.SettingsViewModel
 import org.nsh07.pomodoro.ui.theme.TomatoTheme
-import org.nsh07.pomodoro.ui.timerScreen.viewModel.TimerViewModel
 import org.nsh07.pomodoro.utils.toColor
 
 class MainActivity : ComponentActivity() {
 
-    private val timerViewModel: TimerViewModel by viewModels(factoryProducer = { TimerViewModel.Factory })
     private val settingsViewModel: SettingsViewModel by viewModels(factoryProducer = { SettingsViewModel.Factory })
 
     private val appContainer by lazy {
@@ -62,6 +60,8 @@ class MainActivity : ComponentActivity() {
 
             val seed = preferencesState.colorScheme.toColor()
 
+            val isPlus by settingsViewModel.isPlus.collectAsStateWithLifecycle()
+
             TomatoTheme(
                 darkTheme = darkTheme,
                 seedColor = seed,
@@ -73,7 +73,7 @@ class MainActivity : ComponentActivity() {
                 }
 
                 AppScreen(
-                    timerViewModel = timerViewModel,
+                    isPlus = isPlus,
                     isAODEnabled = preferencesState.aodEnabled,
                     setTimerFrequency = {
                         appContainer.appTimerRepository.timerFrequency = it

app/src/main/java/org/nsh07/pomodoro/TomatoApplication.kt

@@ -1,8 +1,26 @@
+/*
+ * Copyright (c) 2025 Nishant Mishra
+ *
+ * This file is part of Tomato - a minimalist pomodoro timer for Android.
+ *
+ * Tomato 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.
+ *
+ * Tomato 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 Tomato.
+ * If not, see <https://www.gnu.org/licenses/>.
+ */
+
 package org.nsh07.pomodoro
 
 import android.app.Application
 import android.app.NotificationChannel
 import android.app.NotificationManager
+import org.nsh07.pomodoro.billing.initializePurchases
 import org.nsh07.pomodoro.data.AppContainer
 import org.nsh07.pomodoro.data.DefaultAppContainer
 
@@ -12,6 +30,8 @@ class TomatoApplication : Application() {
         super.onCreate()
         container = DefaultAppContainer(this)
 
+        initializePurchases(this)
+
         val notificationChannel = NotificationChannel(
             "timer",
             getString(R.string.timer_progress),

app/src/main/java/org/nsh07/pomodoro/billing/BillingManager.kt

@@ -0,0 +1,24 @@
+/*
+ * Copyright (c) 2025 Nishant Mishra
+ *
+ * This file is part of Tomato - a minimalist pomodoro timer for Android.
+ *
+ * Tomato 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.
+ *
+ * Tomato 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 Tomato.
+ * If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package org.nsh07.pomodoro.billing
+
+import kotlinx.coroutines.flow.StateFlow
+
+interface BillingManager {
+    val isPlus: StateFlow<Boolean>
+}

app/src/main/java/org/nsh07/pomodoro/data/AppContainer.kt

@@ -26,6 +26,8 @@ import androidx.core.app.NotificationCompat
 import androidx.core.app.NotificationManagerCompat
 import kotlinx.coroutines.flow.MutableStateFlow
 import org.nsh07.pomodoro.R
+import org.nsh07.pomodoro.billing.BillingManager
+import org.nsh07.pomodoro.billing.BillingManagerProvider
 import org.nsh07.pomodoro.service.addTimerActions
 import org.nsh07.pomodoro.ui.timerScreen.viewModel.TimerState
 import org.nsh07.pomodoro.utils.millisecondsToStr
@@ -34,6 +36,7 @@ interface AppContainer {
     val appPreferenceRepository: AppPreferenceRepository
     val appStatRepository: AppStatRepository
     val appTimerRepository: AppTimerRepository
+    val billingManager: BillingManager
     val notificationManager: NotificationManagerCompat
     val notificationManagerService: NotificationManager
     val notificationBuilder: NotificationCompat.Builder
@@ -54,6 +57,8 @@ class DefaultAppContainer(context: Context) : AppContainer {
 
     override val appTimerRepository: AppTimerRepository by lazy { AppTimerRepository() }
 
+    override val billingManager: BillingManager by lazy { BillingManagerProvider.manager }
+
     override val notificationManager: NotificationManagerCompat by lazy {
         NotificationManagerCompat.from(context)
     }

app/src/main/java/org/nsh07/pomodoro/ui/AppScreen.kt

@@ -41,8 +41,10 @@ import androidx.compose.material3.Text
 import androidx.compose.material3.adaptive.currentWindowAdaptiveInfo
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
 import androidx.compose.runtime.rememberUpdatedState
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.platform.LocalContext
 import androidx.compose.ui.platform.LocalLayoutDirection
@@ -54,6 +56,7 @@ import androidx.navigation3.runtime.entryProvider
 import androidx.navigation3.runtime.rememberNavBackStack
 import androidx.navigation3.ui.NavDisplay
 import androidx.window.core.layout.WindowSizeClass
+import org.nsh07.pomodoro.billing.TomatoPlusPaywallDialog
 import org.nsh07.pomodoro.service.TimerService
 import org.nsh07.pomodoro.ui.settingsScreen.SettingsScreenRoot
 import org.nsh07.pomodoro.ui.statsScreen.StatsScreenRoot
@@ -65,10 +68,11 @@ import org.nsh07.pomodoro.ui.timerScreen.viewModel.TimerViewModel
 @OptIn(ExperimentalMaterial3Api::class, ExperimentalMaterial3ExpressiveApi::class)
 @Composable
 fun AppScreen(
-    modifier: Modifier = Modifier,
-    timerViewModel: TimerViewModel = viewModel(factory = TimerViewModel.Factory),
     isAODEnabled: Boolean,
-    setTimerFrequency: (Float) -> Unit
+    isPlus: Boolean,
+    setTimerFrequency: (Float) -> Unit,
+    modifier: Modifier = Modifier,
+    timerViewModel: TimerViewModel = viewModel(factory = TimerViewModel.Factory)
 ) {
     val context = LocalContext.current
 
@@ -91,6 +95,7 @@ fun AppScreen(
             }
         }
 
+    var showPaywall by remember { mutableStateOf(false) }
 
     Scaffold(
         bottomBar = {
@@ -218,6 +223,7 @@ fun AppScreen(
 
                     entry<Screen.Settings.Main> {
                         SettingsScreenRoot(
+                            setShowPaywall = { showPaywall = it },
                             modifier = modifier.padding(
                                 start = contentPadding.calculateStartPadding(layoutDirection),
                                 end = contentPadding.calculateEndPadding(layoutDirection),
@@ -240,4 +246,5 @@ fun AppScreen(
             )
         }
     }
+    if (showPaywall) TomatoPlusPaywallDialog(isPlus = isPlus) { showPaywall = false }
 }

app/src/main/java/org/nsh07/pomodoro/ui/settingsScreen/SettingsScreen.kt

@@ -17,6 +17,7 @@
 
 package org.nsh07.pomodoro.ui.settingsScreen
 
+import android.annotation.SuppressLint
 import android.content.Intent
 import android.net.Uri
 import androidx.compose.animation.fadeIn
@@ -25,19 +26,26 @@ import androidx.compose.animation.slideInHorizontally
 import androidx.compose.animation.slideOutHorizontally
 import androidx.compose.animation.togetherWith
 import androidx.compose.foundation.background
+import androidx.compose.foundation.clickable
 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.height
 import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.layout.size
+import androidx.compose.foundation.layout.width
 import androidx.compose.foundation.lazy.LazyColumn
 import androidx.compose.foundation.lazy.itemsIndexed
+import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.foundation.text.input.TextFieldState
 import androidx.compose.material3.ExperimentalMaterial3Api
 import androidx.compose.material3.ExperimentalMaterial3ExpressiveApi
 import androidx.compose.material3.Icon
 import androidx.compose.material3.LocalTextStyle
+import androidx.compose.material3.MaterialTheme.colorScheme
+import androidx.compose.material3.MaterialTheme.typography
 import androidx.compose.material3.SliderState
 import androidx.compose.material3.Text
 import androidx.compose.material3.TopAppBar
@@ -50,6 +58,7 @@ import androidx.compose.runtime.saveable.rememberSaveable
 import androidx.compose.runtime.snapshots.SnapshotStateList
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.draw.clip
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.input.nestedscroll.nestedScroll
 import androidx.compose.ui.platform.LocalContext
@@ -80,6 +89,7 @@ import org.nsh07.pomodoro.ui.theme.CustomColors.topBarColors
 @OptIn(ExperimentalMaterial3Api::class)
 @Composable
 fun SettingsScreenRoot(
+    setShowPaywall: (Boolean) -> Unit,
     modifier: Modifier = Modifier,
     viewModel: SettingsViewModel = viewModel(factory = SettingsViewModel.Factory)
 ) {
@@ -102,6 +112,7 @@ fun SettingsScreenRoot(
         viewModel.longBreakTimeTextFieldState
     }
 
+    val isPlus by viewModel.isPlus.collectAsStateWithLifecycle()
     val alarmEnabled by viewModel.alarmEnabled.collectAsStateWithLifecycle(true)
     val vibrateEnabled by viewModel.vibrateEnabled.collectAsStateWithLifecycle(true)
     val dndEnabled by viewModel.dndEnabled.collectAsStateWithLifecycle(false)
@@ -119,6 +130,7 @@ fun SettingsScreenRoot(
     }
 
     SettingsScreen(
+        isPlus = isPlus,
         preferencesState = preferencesState,
         backStack = backStack,
         focusTimeInputFieldState = focusTimeInputFieldState,
@@ -143,13 +155,16 @@ fun SettingsScreenRoot(
         },
         onThemeChange = viewModel::saveTheme,
         onColorSchemeChange = viewModel::saveColorScheme,
+        setShowPaywall = setShowPaywall,
         modifier = modifier
     )
 }
 
+@SuppressLint("LocalContextGetResourceValueCall")
 @OptIn(ExperimentalMaterial3Api::class, ExperimentalMaterial3ExpressiveApi::class)
 @Composable
 private fun SettingsScreen(
+    isPlus: Boolean,
     preferencesState: PreferencesState,
     backStack: SnapshotStateList<Screen.Settings>,
     focusTimeInputFieldState: TextFieldState,
@@ -168,6 +183,7 @@ private fun SettingsScreen(
     onAlarmSoundChanged: (Uri?) -> Unit,
     onThemeChange: (String) -> Unit,
     onColorSchemeChange: (Color) -> Unit,
+    setShowPaywall: (Boolean) -> Unit,
     modifier: Modifier = Modifier
 ) {
     val context = LocalContext.current
@@ -217,6 +233,39 @@ private fun SettingsScreen(
                     ) {
                         item { Spacer(Modifier.height(12.dp)) }
 
+                        if (!isPlus) item {
+                            Row(
+                                verticalAlignment = Alignment.CenterVertically,
+                                modifier = Modifier
+                                    .clip(CircleShape)
+                                    .background(colorScheme.primary)
+                                    .padding(16.dp)
+                                    .clickable { setShowPaywall(true) }
+                            ) {
+                                Icon(
+                                    painterResource(R.drawable.tomato_logo_notification),
+                                    null,
+                                    tint = colorScheme.onPrimary,
+                                    modifier = Modifier
+                                        .size(24.dp)
+                                )
+                                Spacer(Modifier.width(8.dp))
+                                Text(
+                                    "Get Tomato+",
+                                    style = typography.titleLarge,
+                                    fontFamily = robotoFlexTopBar,
+                                    color = colorScheme.onPrimary
+                                )
+                                Spacer(Modifier.weight(1f))
+                                Icon(
+                                    painterResource(R.drawable.arrow_forward_big),
+                                    null,
+                                    tint = colorScheme.onPrimary
+                                )
+                            }
+                            Spacer(Modifier.height(14.dp))
+                        }
+
                         item { AboutCard() }
 
                         item { Spacer(Modifier.height(12.dp)) }

app/src/main/java/org/nsh07/pomodoro/ui/settingsScreen/viewModel/SettingsViewModel.kt

@@ -40,17 +40,21 @@ import kotlinx.coroutines.flow.distinctUntilChanged
 import kotlinx.coroutines.flow.update
 import kotlinx.coroutines.launch
 import org.nsh07.pomodoro.TomatoApplication
+import org.nsh07.pomodoro.billing.BillingManager
 import org.nsh07.pomodoro.data.AppPreferenceRepository
 import org.nsh07.pomodoro.data.TimerRepository
 import org.nsh07.pomodoro.ui.Screen
 
 @OptIn(FlowPreview::class, ExperimentalMaterial3Api::class)
 class SettingsViewModel(
+    private val billingManager: BillingManager,
     private val preferenceRepository: AppPreferenceRepository,
     private val timerRepository: TimerRepository,
 ) : ViewModel() {
     val backStack = mutableStateListOf<Screen.Settings>(Screen.Settings.Main)
 
+    val isPlus = billingManager.isPlus
+
     private val _preferencesState = MutableStateFlow(PreferencesState())
     val preferencesState = _preferencesState.asStateFlow()
 
@@ -237,8 +241,10 @@ class SettingsViewModel(
                 val application = (this[APPLICATION_KEY] as TomatoApplication)
                 val appPreferenceRepository = application.container.appPreferenceRepository
                 val appTimerRepository = application.container.appTimerRepository
+                val appBillingManager = application.container.billingManager
 
                 SettingsViewModel(
+                    billingManager = appBillingManager,
                     preferenceRepository = appPreferenceRepository,
                     timerRepository = appTimerRepository,
                 )

app/src/play/java/org/nsh07/pomodoro/billing/PlayBillingManager.kt

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2025 Nishant Mishra
+ *
+ * This file is part of Tomato - a minimalist pomodoro timer for Android.
+ *
+ * Tomato 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.
+ *
+ * Tomato 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 Tomato.
+ * If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package org.nsh07.pomodoro.billing
+
+import android.util.Log
+import com.revenuecat.purchases.Purchases
+import com.revenuecat.purchases.getCustomerInfoWith
+import com.revenuecat.purchases.interfaces.UpdatedCustomerInfoListener
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
+
+private const val ENTITLEMENT_ID = "plus"
+
+/**
+ * Google Play implementation of BillingManager
+ */
+class PlayBillingManager : BillingManager {
+    private val _isPlus = MutableStateFlow(false)
+    override val isPlus = _isPlus.asStateFlow()
+
+    private val purchases by lazy { Purchases.sharedInstance }
+
+    init {
+        purchases.updatedCustomerInfoListener =
+            UpdatedCustomerInfoListener { customerInfo ->
+                _isPlus.value = customerInfo.entitlements[ENTITLEMENT_ID]?.isActive == true
+            }
+
+        // Fetch initial customer info
+        purchases.getCustomerInfoWith(
+            onSuccess = { customerInfo ->
+                _isPlus.value = customerInfo.entitlements[ENTITLEMENT_ID]?.isActive == true
+            },
+            onError = { error ->
+                Log.e("GooglePlayPaywallManager", "Error fetching customer info: $error")
+            }
+        )
+    }
+}
+
+object BillingManagerProvider {
+    val manager: BillingManager = PlayBillingManager()
+}

app/src/play/java/org/nsh07/pomodoro/billing/TomatoPlusPaywallDialog.kt

@@ -0,0 +1,63 @@
+/*
+ * Copyright (c) 2025 Nishant Mishra
+ *
+ * This file is part of Tomato - a minimalist pomodoro timer for Android.
+ *
+ * Tomato 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.
+ *
+ * Tomato 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 Tomato.
+ * If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package org.nsh07.pomodoro.billing
+
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.FilledTonalIconButton
+import androidx.compose.material3.Icon
+import androidx.compose.material3.Scaffold
+import androidx.compose.runtime.Composable
+import androidx.compose.runtime.remember
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.res.painterResource
+import androidx.compose.ui.unit.dp
+import com.revenuecat.purchases.ui.revenuecatui.Paywall
+import com.revenuecat.purchases.ui.revenuecatui.PaywallOptions
+import com.revenuecat.purchases.ui.revenuecatui.customercenter.CustomerCenter
+import org.nsh07.pomodoro.R
+
+@Composable
+fun TomatoPlusPaywallDialog(
+    isPlus: Boolean,
+    onDismiss: () -> Unit
+) {
+    val paywallOptions = remember {
+        PaywallOptions.Builder(dismissRequest = onDismiss)
+            .build()
+    }
+
+    Scaffold { innerPadding ->
+        if (!isPlus) {
+            Paywall(paywallOptions)
+
+            FilledTonalIconButton(
+                onClick = onDismiss,
+                modifier = Modifier
+                    .padding(innerPadding)
+                    .padding(16.dp)
+            ) {
+                Icon(
+                    painterResource(R.drawable.arrow_back),
+                    null
+                )
+            }
+        } else {
+            CustomerCenter(onDismiss = onDismiss)
+        }
+    }
+}

app/src/play/java/org/nsh07/pomodoro/billing/initializePurchases.kt

@@ -0,0 +1,30 @@
+/*
+ * Copyright (c) 2025 Nishant Mishra
+ *
+ * This file is part of Tomato - a minimalist pomodoro timer for Android.
+ *
+ * Tomato 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.
+ *
+ * Tomato 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 Tomato.
+ * If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package org.nsh07.pomodoro.billing
+
+import android.content.Context
+import com.revenuecat.purchases.Purchases
+import com.revenuecat.purchases.PurchasesConfiguration
+
+fun initializePurchases(context: Context) {
+    Purchases.configure(
+        PurchasesConfiguration
+            .Builder(context, "goog_jBpRIBjTYvhKYluCqkPXSHbuFbX")
+            .build()
+    )
+}

gradle/libs.versions.toml

@@ -12,7 +12,7 @@ ksp = "2.2.20-2.0.4"
 lifecycleRuntimeKtx = "2.9.4"
 materialKolor = "3.0.1"
 navigation3 = "1.0.0-beta01"
-purchases = "9.12.0"
+revenuecat = "9.12.0"
 room = "2.8.3"
 vico = "2.2.1"
 
@@ -40,7 +40,8 @@ androidx-ui-tooling = { group = "androidx.compose.ui", name = "ui-tooling" }
 androidx-ui-tooling-preview = { group = "androidx.compose.ui", name = "ui-tooling-preview" }
 junit = { group = "junit", name = "junit", version.ref = "junit" }
 material-kolor = { module = "com.materialkolor:material-kolor", version.ref = "materialKolor" }
-purchases = { module = "com.revenuecat.purchases:purchases", version.ref = "purchases" }
+revenuecat-purchases = { module = "com.revenuecat.purchases:purchases", version.ref = "revenuecat" }
+revenuecat-purchases-ui = { module = "com.revenuecat.purchases:purchases-ui", version.ref = "revenuecat" }
 vico-compose-m3 = { group = "com.patrykandpatrick.vico", name = "compose-m3", version.ref = "vico" }
 
 [plugins]