Add UpdateInfoListener

MainActivity.java

mUpdateManager.addUpdateInfoListener(new UpdateInfoListener() {
    @Override
    public void onReceiveVersionCode(final int code) {
        // You can get the available version code of the apk in Google Play
        // Do something here
    }

    @Override
    public void onReceiveStalenessDays(final int days) {
        // Number of days passed since the user was notified of an update through the Google Play
        // If the user hasn't notified this will return -1 as days
        // You can decide the type of update you want to call
    }
});