// returns IP
static S waitForPhone() {
  print("Waiting for phone to come online...");
  S phoneIP = null;
  while licensed {
    L<S> possiblePhones = empBlast_findAndroidPhone();
    if (l(possiblePhones) > 1) print("Possible phones: " + struct(possiblePhones));
    phoneIP = first(possiblePhones);
    if (phoneIP != null) break;
    sleepSeconds(1);
  }
  print("Using phone: " + phoneIP);
  ret phoneIP;
}