diff --git a/lib/blocs/time_bloc.dart b/lib/blocs/time_bloc.dart
index fc9d28d..5ddd035 100644
--- a/lib/blocs/time_bloc.dart
+++ b/lib/blocs/time_bloc.dart
@@ -25,7 +25,7 @@ class TimerBloc extends Bloc<TimerEvent, TimerState> {
     on<TimerTicked>(_onTicked);
   }
 
-  static const List<int> times = [1, 15, 20, 25, 30, 35];
+  static const List<int> times = [15, 20, 25, 30, 35];
   final Ticker _ticker;
   final SharedPreferences prefs;
   final int initDuration;
diff --git a/lib/main.dart b/lib/main.dart
index c56168d..8061844 100644
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -1,5 +1,4 @@
 import 'dart:async';
-import 'dart:io';
 import 'dart:isolate';
 import 'dart:ui';
 
@@ -57,6 +56,7 @@ Future<void> onService(args) async {
   final service = FlutterBackgroundService();
   final servicePort = ReceivePort();
   var isServiceRunning = await service.isRunning();
+  StreamSubscription<int>? tickerSubscription;
   const ticker = Ticker();
 
   Future<void> disposeService(String message) async {
@@ -66,23 +66,10 @@ Future<void> onService(args) async {
     }
   }
 
-  servicePort.listen((message) async {
-    if (message == 'stopService') {
-      await disposeService(message);
-    } else if (message is List) {
-      ticker.tick(ticks: message[0]).listen((duration) => service.invoke(
-          'sendTime', {'currentTime': duration, 'isBreak': message[1]}));
-    } else if (message == 'exit') {
-      await disposeService('stopService');
-      exit(0);
-    }
-  });
-  args[2].send(servicePort.sendPort);
-
   if (!isServiceRunning) {
     await service.startService();
   }
-  ticker.tick(ticks: args[0]).listen((duration) async {
+  tickerSubscription = ticker.tick(ticks: args[0]).listen((duration) async {
     var isServiceRunning = await service.isRunning();
     if (isServiceRunning) {
       service.invoke('sendTime', {'currentTime': duration, 'isBreak': args[1]});
@@ -90,6 +77,20 @@ Future<void> onService(args) async {
       args[2].send('pause');
     }
   });
+
+  servicePort.listen((message) async {
+    if (message == 'stopService') {
+      await disposeService(message);
+    } else if (message is List) {
+      tickerSubscription = ticker.tick(ticks: message[0]).listen((duration) =>
+          service.invoke(
+              'sendTime', {'currentTime': duration, 'isBreak': message[1]}));
+    } else if (message == 'exit') {
+      await disposeService('stopService');
+      tickerSubscription!.cancel();
+    }
+  });
+  args[2].send(servicePort.sendPort);
 }
 
 Future<void> initializeService() async {
diff --git a/lib/screens/home_screen.dart b/lib/screens/home_screen.dart
index 3c86044..5676206 100644
--- a/lib/screens/home_screen.dart
+++ b/lib/screens/home_screen.dart
@@ -1,6 +1,7 @@
 import 'dart:async';
 
 import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
 import 'package:flutter_bloc/flutter_bloc.dart';
 import 'package:google_mobile_ads/google_mobile_ads.dart';
 import 'package:pomotimer/ad_helper.dart';
@@ -22,7 +23,7 @@ class HomeScreen extends StatefulWidget {
   State<HomeScreen> createState() => _HomeScreenState();
 }
 
-class _HomeScreenState extends State<HomeScreen> {
+class _HomeScreenState extends State<HomeScreen> with WidgetsBindingObserver {
   static const settingTypeString = ['ROUND', 'TIME', 'COUNT'];
   FixedExtentScrollController listWheelController =
       FixedExtentScrollController();
@@ -33,10 +34,12 @@ class _HomeScreenState extends State<HomeScreen> {
   int round = 0;
   int time = 0;
   int index = 0;
+  AppLifecycleState lifecycleState = AppLifecycleState.inactive;
 
   @override
   void dispose() {
     _bannerAd?.dispose();
+    WidgetsBinding.instance.addObserver(this);
     super.dispose();
   }
 
@@ -59,6 +62,13 @@ class _HomeScreenState extends State<HomeScreen> {
         },
       ),
     ).load();
+    WidgetsBinding.instance.addObserver(this);
+  }
+
+  @override
+  void didChangeAppLifecycleState(AppLifecycleState state) {
+    lifecycleState = state;
+    super.didChangeAppLifecycleState(state);
   }
 
   Future controllerInit() async {
@@ -86,22 +96,24 @@ class _HomeScreenState extends State<HomeScreen> {
     btTextController.text = ((getFromRepo('breakTime') - 3) ~/ 60).toString();
 
     void showAlertScreen(String text) async {
-      if (mounted) {
-        Navigator.of(context).push(
-          MaterialPageRoute(
-            builder: (context) {
-              return AlertScreen(
-                text: text,
-              );
-            },
-          ),
-        );
+      if (lifecycleState == AppLifecycleState.inactive) {
+        if (mounted) {
+          Navigator.of(context).push(
+            MaterialPageRoute(
+              builder: (context) {
+                return AlertScreen(
+                  text: text,
+                );
+              },
+            ),
+          );
+        }
+        await Future.delayed(const Duration(seconds: 3));
+        if (mounted) Navigator.of(context).pop();
       }
-      await Future.delayed(const Duration(seconds: 3));
-      if (mounted) Navigator.of(context).pop();
     }
 
-    Future<bool> onWillPop() {
+    Future<bool> onWillPop() async {
       DateTime now = DateTime.now();
       if (currentBackPressTime == null ||
           now.difference(currentBackPressTime!) > const Duration(seconds: 2)) {
@@ -111,6 +123,7 @@ class _HomeScreenState extends State<HomeScreen> {
       final isolatePort = context.read<TimerBloc>().isolatePort;
       if (isolatePort != null) {
         isolatePort.send('exit');
+        await SystemNavigator.pop();
       }
       return Future.value(true);
     }
diff --git a/pubspec.yaml b/pubspec.yaml
index a855b3b..a1a2ff0 100644
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -17,7 +17,7 @@ publish_to: 'none' # Remove this line if you wish to publish to pub.dev
 # https://developer.apple.com/library/archive/documentation/General/Reference/InfoPlistKeyReference/Articles/CoreFoundationKeys.html
 # In Windows, build-name is used as the major, minor, and patch parts
 # of the product and file versions while build-number is used as the build suffix.
-version: 1.19.0+19
+version: 1.20.0+20
 
 environment:
   sdk: '>=2.19.0 <3.0.0'