Here is the message i get when i run flutter app on my android mobile and also i see just black screen on my mobile, though the app gets installed i can see icon of that
Launching lib\main.dart on SM A217F in debug mode...
Running Gradle task 'assembleDebug'...
Note: C:\Users\RK\AppData\Local\Pub\Cache\hosted\pub.dev\local_auth_android-1.0.19\android\src\main\java\io\flutter\plugins\localauth\LocalAuthPlugin.java uses or overrides a deprecated API.
Note: Recompile with -Xlint:deprecation for details.
√ Built build\app\outputs\flutter-apk\app-debug.apk.
Installing build\app\outputs\flutter-apk\app-debug.apk...
Debug service listening on ws://127.0.0.1:54767/IQmQ4n-nj04=/ws
Syncing files to device SM A217F...
I/xample.untitle(22299): Compiler allocated 4564KB to compile void android.view.ViewRootImpl.performTraversals()
E/flutter (22299):
[ERROR:flutter/runtime/dart_vm_initializer.cc(41)] Unhandled Exception: [core/duplicate-app] A Firebase App named "[DEFAULT]" already exists
E/flutter (22299): #0 MethodChannelFirebase.initializeApp (package:firebase_core_platform_interface/src/method_channel/method_channel_firebase.dart:134:11)
E/flutter (22299): <asynchronous suspension>
E/flutter (22299): #1 Firebase.initializeApp (package:firebase_core/src/firebase.dart:43:31)
E/flutter (22299): <asynchronous suspension>
E/flutter (22299): #2 main (package:untitled/main.dart:15:3)
E/flutter (22299): <asynchronous suspension>
E/flutter (22299):
I tried to run app on mobile via usb, my developer mode is ON, app runs in chrome web well but when i move to mobile through usb i get only black blank screen.
Actually the solution for appearing dark screen is go to file, open then select project and open android part of it... now run this one it opens app in mobile(android)