I am looking for Options to send push-notifications from laravel-php-web applications to an Android smartwatch. But I do not want to use any cloud service like Google Cloud Messaging or Google Firebase etc, because I don't want to share the sent sensible data with Google or another company.
Do you maybe have any suggestions about how to implement something like this?
If you want to avoid using Google Firebase, you could make use of another service like Pusher or PubNub. You could also make your own Pub/Sub server with Socket.io or the new Laravel-WebSockets library, a library that use the same API as Pusher (for easy integration). This last option is the one I'd recommend. You can check this channel for an in-deep tutorial.
In order to make Laravel-WebSockets to work with Android, just use the Pusher library for Android and set your host variables and keys in the config.