Device IMEI

  /Need Permission
  <uses-permission android:name="android.permission.READ_PHONE_STATE" />

  //Global veriable
  private String deviceImei;

  //Get device IMEI
  TelephonyManager mTelephonyManager = (TelephonyManager) getSystemService(Context.TELEPHONY_SERVICE);
  assert mTelephonyManager != null;
  deviceImei = mTelephonyManager.getDeviceId();
  Log.e(TAG, "IMEI: " + deviceImei);

  //Need this checking because some emulator return "---" as IMEI
  if (deviceImei != null && deviceImei.matches("[0-9]+")) {

  } else
    Utils.showAlert("Info", "This app doesn't support in your device.", mContext, "Ok");