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Two apps after react-native run-android

I'm making a react native app and earlier it was working fine but now when I run "react-native run-android", after the successful install and launch, I can see two apps in the simulator and both of them are working fine.
So, any ideas why I'm seeing 2 apps or should I say why I'm getting an extra duplicate app installed?

I think you added splash screen in your app after it you have this problem, first go to this Dir: android/app/src/main/AndroidManifest.xml if you add two time something like this
<activity
android:name=".SplashActivity"
android:theme="#style/SplashTheme"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity> -->
it will render two times and build two apps on your device.
in my file
AndroidManifest.xml
<!-- remove just first part the activity, but i comment this part -->
<!-- <activity
android:name=".SplashActivity"
android:theme="#style/SplashTheme"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity> -->
<activity
android:name=".MainActivity"
android:label="#string/app_name"
android:theme="#style/SplashTheme"
android:configChanges="keyboard|keyboardHidden|orientation|screenSize"
android:windowSoftInputMode="adjustResize">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>

The problem is due to multiple category LAUNCHER in both splash and main activity.
<category android:name="android.intent.category.LAUNCHER" />
The solution with both SplashActivity and MainActivity is to change
<category android:name="android.intent.category.LAUNCHER" />
to
<category android:name="android.intent.category.DEFAULT" />
in MainActivity.
The file with both .SplashActivity and .MainActivity looks like this;
<activity
android:name=".SplashActivity"
android:theme="#style/SplashTheme"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".MainActivity"
android:label="#string/app_name"
android:configChanges="keyboard|keyboardHidden|orientation|screenSize"
android:windowSoftInputMode="adjustResize"
android:exported="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.BROWSABLE" />
</intent-filter>
</activity>

I had this issue as well. It turns out one of RN lib I installed created an extra <activity /> and <intent-filter />tags. Just check your AndroidManifest.xml.
My source: Running app gives 2 app icons in Android Studio - newbie

Change this
<activity
android:name=".SplashActivity"
android:theme="#style/SplashTheme"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".MainActivity"
android:label="#string/app_name"
android:configChanges="keyboard|keyboardHidden|orientation|screenSize"
android:windowSoftInputMode="adjustResize"
android:exported="true"
>
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
To
<activity
android:name=".SplashActivity"
android:theme="#style/SplashTheme"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".MainActivity"
android:label="#string/app_name"
android:configChanges="keyboard|keyboardHidden|orientation|screenSize"
android:windowSoftInputMode="adjustResize"
android:exported="true"
/>
Basically you have two intent-filters delete one
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>

To add to the answer Aras posted above, for me the issue was specifically with the extra intent-filter attributes which were labeled 'MAIN' and 'LAUNCHER'. You can't have more than one occurrence of those without creating duplicate apps, it seems.
<activity
android:name=".SplashActivity"
android:theme="#style/SplashTheme"
android:label="#string/app_name">
<!-- You'll either want to remove this section, or ensure that it does not exist in any other activities. -->
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>

Check the package name of the installed apps.

android: what's the error？

I got this warning from console when running my application on my phone. And my phone haven't any response.
No Launcher activity found! [2016-03-11 14:44:59 - ActivityTest] The
launch will only sync the application package on the device!

Check this -
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
You should set action main is caps
i.e <action android:name="android.intent.action.MAIN" />

I think your error comes because you declare this row in your Manifest wrong
<action android:name="android.intent.action.Main" />
Your Manifest must be some like this
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme">
<activity
android:name=".FirstActivity"
android:label="This is FirstActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN"/> <-- MAIN with upper case
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
</application>
This two lines in your Manifest always must look exactly like that.They are not classes in your app.They are actions that are happening.
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />

App not showing in launcher

After installing an app via the run command on Android Studio, the app launches correctly, I can see it in the applications list and account manager.
The problem is that it doesn't show up at all in the app launcher. (I have Google Launcher installed on the Nexus 5 device which I am testing on and everything was working fine before 6.0.1).
App name is "Pumpkin".
Here is the manifest
And here's the screenshot where Pumpkin's supposed to fit.

Your Intent-Filter seems to be wrong. Change to:
<activity
android:name="com.pumpkin.activities.SplashScreenActivity"
android:label="#string/app_name"
android:screenOrientation="portrait" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter>
<data android:scheme="pumpkin.com" android:host="open" />
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.BROWSABLE" />
</intent-filter>
</activity>

Add this intent filter to your splash screen activity:
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>

your deep link
https://sureassure.com
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".Main2Activity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
<category android:name="android.intent.category.BROWSABLE" />
<data android:scheme="https"
android:host="sureassure.com" // website name
/>
</intent-filter>
</activity>
</application>

My app icon does not appear in the emulator home screen

I want specific ordered reasons why my app icon does not appear, I can run it on the emulator yet and I need to know what's wrong with my app? I'm a beginner my code is so simple, though I can't find why is this happening.
Here is my manifest:
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".Splash"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.launcher" />
</intent-filter>
</activity>
<activity
android:name=".MyActivity"
android:label="#string/app_name">
<intent-filter>
<action android:name="com.example.hp.app2.MyActivity" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>

Instead of
<category android:name="android.intent.category.launcher" />
it must be
<category android:name="android.intent.category.LAUNCHER" />

My App Installs Two Applications - Android

Whenever I try to run my App, it installs two app in the emulator/device. I only want to Install my Main Activity, but the Splash Activity installs also. I know the problem is in the Manifest. Can anyone help me please? Here is my code:
<activity
android:name="com.android.upcurrents.launcher.SplashActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.android.upcurrents.MainActivity"
android:label="#string/app_name" />

You need to have only one activity to be declared as the launcher. So, remove the intent-filter from within the SplashActivity's tag, and add it to your MainActivity. The Launcher intent-filter should be present in only one of the activities in your manifest file.

It installs based on the intent filter you have provided.
Remove the following intent filter from SplashActivity and then put it in Main Activity
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>

try this:
<activity
android:name="com.android.upcurrents.launcher.SplashActivity"
android:label="#string/app_name" >
</activity>
<activity
android:name="com.android.upcurrents.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>

I had this same problem but I fixed it with the making sure you only have one activity with:
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
In my code I had two activities with that intent-filter, which caused two applications to be installed on my device.

We have the same problem but i fixed it this way
before my code below in manifest
<application
android:debuggable="true"
android:allowBackup="true">
<activity android:name=".SplashActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.noupdate.apptest_noupdate.MainActivity"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
Notice that in the SplashActivity inside the intent is this code
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
i only deleted the category
<category android:name="android.intent.category.LAUNCHER" />
So after i deleted the intent-filter category in splash it didn't install two app icon but only one for main the code will be like this notice that the intent-filter category is deleted
<application
android:debuggable="true"
android:allowBackup="true">
<activity android:name=".SplashActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
</intent-filter>
</activity>
<activity
android:name="com.noupdate.apptest_noupdate.MainActivity"
android:icon="#drawable/ic_launcher"
android:theme="#android:style/Theme.NoTitleBar"
android:label="#string/app_name">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
it really helps