It’s my understanding that in order to get the device ID, you have to be an identified developer. This is a security mechanism to prevent unauthorized apps from stealing device information. FCM (the replacement for GCM) has a way to trigger notifications to be sent to iOS devices using the FCM APIs, but my understanding is that it still requires an APN certificate specific to the application bundle identifier… it’s just that the place the certificate is registered is on Google’s servers rather than on the OpenHAB cloud instance.
