SplashActivity.java

public class SplashActivity extends AppCompatActivity {

    private static final int REQ_CODE = 23;

    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        setTheme(R.style.AppTheme);
        super.onCreate(savedInstanceState);
        if (shouldFinishActivity()) {
            return;
        }
        setContentView(R.layout.activity_splash);

        onActivityOpened();
    }

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        if (requestCode == REQ_CODE) {
            finish();
        }
    }

    @Override
    protected void onNewIntent(Intent intent) {
        super.onNewIntent(intent);
        if (shouldFinishActivity()) {
            return;
        }

        onActivityOpened();
    }

    /*
     * http://stackoverflow.com/a/23220151/3423932
     *
     * with launchMode singleTask | singleInstance, pressing home from inner activity and opening app through launcher icon
     * always opens launcher activity instead of resuming old activity. As a workaround, we finish the
     * activity if it is not root activity
     * */
    private boolean shouldFinishActivity() {
        if (ActivityLifeCycleCallback.Companion.getActivityCount() > 1) {
            finish();
            return true;
        }
        if (!isTaskRoot()
                && getIntent().hasCategory(Intent.CATEGORY_LAUNCHER)
                && getIntent().getAction() != null
                && getIntent().getAction().equals(Intent.ACTION_MAIN)) {

            finish();
            return true;
        }
        return false;
    }

    private void onActivityOpened() {
        Class<? extends AppCompatActivity> activityClass;
        if (PreferencesUtil.INSTANCE.isOnBoardingShownAlready()) {
            activityClass = MainActivity.class;
        } else {
            activityClass = OnBoardingActivity.class;
        }
        Intent intent = new Intent(getIntent().getAction(), getIntent().getData(), this, activityClass);
        startActivityForResult(intent, REQ_CODE);
        overridePendingTransition(0, 0);
    }
}