Finish all activities at a time

There is a finishAffinity() method in Activity that will finish the current activity and all parent activities, but it works only in Android 4.1 or higher.

For API 16+, use

finishAffinity();

For lower (Android 4.1 lower), use

ActivityCompat.finishAffinity(YourActivity.this);

The best solution i have found, which is compatible with devices having API level <11

Intent intent = new Intent(getApplicationContext(), HomeActivity.class);
ComponentName cn = intent.getComponent();
Intent mainIntent = IntentCompat.makeRestartActivityTask(cn);
startActivity(mainIntent);

This solution requires Android support library

Whenever you wish to exit all open activities, you should press a button which loads the first Activity that runs when your application starts then clear all the other activities, then have the last remaining activity finish. to do so apply the following code in ur project

Intent intent = new Intent(getApplicationContext(), FirstActivity.class);
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
intent.putExtra("EXIT", true);
startActivity(intent);

The above code finishes all the activities except for FirstActivity. Then we need to finish the FirstActivity's Enter the below code in Firstactivity's oncreate

if (getIntent().getBooleanExtra("EXIT", false)) {
    finish();
}

and you are done....