How to detect if application has been updated or installed

In some cases there is a need to know if user has installed or updated your app. For example to put different texts or something else. To do this you may use code below:

static public boolean isUpdated(Context ctx) {
    PackageInfo packageInfo = null;
    try {
            packageInfo = ctx.getPackageManager().getPackageInfo(ctx.getPackageName(),
                PackageManager.GET_ACTIVITIES);
        } catch (PackageManager.NameNotFoundException e) {
            Log.e(TAG, "Can't get package info");
        }
    return (packageInfo.firstInstallTime != packageInfo.lastUpdateTime);
}