Default [Q] Background Service to check for notifications


I want to create an background-service which loads some data from my server and then create a notification.

I already know how to create the notification and how to load data from the server, but how should I make the background-service?

Another thing is, that the service should get called on 5 o'clock in the morning everyday or on boot complete, if the device was switched off at 5 o'clock.