I wrote an bluetooth app with my bt-connection established in a service, so the connection is still alive when I minimize my app.
But when watching my task manager, my app is still there. And when calling onDestroy in my app, I have to stop my Service.
But other apps like telegram or skype (whatsapp too I think) aren't in my task-manager visible but by having an incoming message they notify me nevertheless.
How is this even possible? How can I write my bluetooth connection like this, that I can really close my app and anyway the incoming messages will be handled?
The other apps might be having some light weight service running in other process which gets the data for the main app.Go to settings->application manager->running processes..you will see all the service..
Other mechanism which apps use is port-directed sms. In such a scenario you don't need any service running.However port directed sms doesnt work on all the phone and for all the apps.