Find if the app is installed from a trusted source

TrustedInstallation.java

public static boolean isTrustedInstallation(Application app) {
  PackageManager packageManager = app.getPackageManager();
  String installerId = packageManager.getInstallerPackageName(app.getPackageName());
  
  if (installerId == null) {
    return false;
  } else if (installerId.contains("aptoide")) {
    return false;
  } else if (installerId.contains("xiaomi")) {
    return false;
  }
  return true;
}