How to get Android application id?

In Android, how do I get the application's id programatically (or by some other method), and how can I communicate with other applications using that id?

If your are looking for the value defined by applicationId in gradle, you can simply use

BuildConfig.APPLICATION_ID 

If by application id, you're referring to package name, you can use the method Context::getPackageName (http://http://developer.android.com/reference/android/content/Context.html#getPackageName%28%29).

In case you wish to communicate with other application, there are multiple ways:

1. Start an activity of another application and send data in the "Extras" of the "Intent"
2. Send a broadcast with specific action/category and send data in the extras
3. If you just need to share structured data, use content provider
4. If the other application needs to continuously run in the background, use Server and "bind" yourself to the service.

If you can elaborate your exact requirement, the community will be able to help you better.

i'm not sure what "application id" you are referring to, but for a unique identifier of your application you can use:

getApplication().getPackageName() method from your current activity

For getting AppId (or package name, how some says), just call this:

But be sure that you importing BuildConfig with your app id packages path

BuildConfig.APPLICATION_ID 

Package name is your android app id .

String appId = BuildConfig.APPLICATION_ID

Or

https://play.google.com/store/apps/details?id=com.whatsapp

App Id = com.whatsapp

Else you can get id of process your application runs in:

final static int android.os.Process.myPid()
Returns the identifier of this process, which can be used with killProcess(int) and sendSignal(int, int).

I am not sure what you need the app/installation ID for, but you can review the existing possibilities in a great article from Android developers:

• http://android-developers.blogspot.com/2011/03/identifying-app-installations.html

To sum up:

• UUID.randomUUID() for creating id on the first time an app runs after installation and simple retrieval afterwards
• TelephonyManager.getDeviceId() for actual device identifier
• Settings.Secure.ANDROID_ID on relatively modern devices

Step 1: Open the Google Play Store

Step 2: Open any App in App Store Example: facebook

Step 3: Click on any App and Look at the Browser link and At the End id=com.facebook.katana&hl=en will be there and [this is your Apps Unique Id.] 3

The PackageInfo.sharedUserId field will show the user Id assigned in the manifest.

If you want two applications to have the same userId, so they can see each other's data and run in the same process, then assign them the same userId in the manifest:

android:sharedUserId="string"

The two packages with the same sharedUserId need to have the same signature too.

I would also recommend reading here for a nudge in the right direction.

If the whole purpose is to communicate data with some other application, use Intent's sendBroadcast methods.

If you are using the new** Gradle build system then getPackageName will oddly return application Id, not package name. So MasterGaurav's answer is correct but he doesn't need to start off with ++

> If by application id, you're referring to package name...

See more about the differences here.

** not so new at this point

++ I realize that his answer made perfect sense in 2011

Android App ES File Explorer shows the Android package name in the User Apps section which is useful for Bitwarden. Bitwarden refers to this as "android application package ID (or package name)".

To track installations, you could for example use a UUID as an identifier, and simply create a new one the first time an app runs after installation. Here is a sketch of a class named “Installation” with one static method Installation.id(Context context). You could imagine writing more installation-specific data into the INSTALLATION file.

public class Installation {
private static String sID = null;
private static final String INSTALLATION = "INSTALLATION";
public synchronized static String id(Context context) {

    if (sID == null) {  
       File installation = new File(context.getFilesDir(), INSTALLATION);
       try {
           if (!installation.exists())
               writeInstallationFile(installation);
           sID = readInstallationFile(installation);
       } catch (Exception e) {
           throw new RuntimeException(e);
       }
    }
   return sID;
}

private static String readInstallationFile(File installation) throws IOException {
   RandomAccessFile f = new RandomAccessFile(installation, "r");
   byte[] bytes = new byte[(int) f.length()];
   f.readFully(bytes);
   f.close();
   return new String(bytes);
}

private static void writeInstallationFile(File installation) throws IOException {
   FileOutputStream out = new FileOutputStream(installation);
   String id = UUID.randomUUID().toString();
   out.write(id.getBytes());
   out.close();
}

}

Yon can see more at https://github.com/MShoaibAkram/Android-Unique-Application-ID