This app was mentioned in 5 comments, with an average of 8.80 upvotes
Well I do have a suggestion but it's off the norm. Islamic athan clocks adjust automatically. There is a time called "shuruq" that is a few moments before sunrise. You could turn off all the other prayer times and set the shuruq alarm to go off 30 mins prior to sunrise.
It may take you a bit of tinkering with, also pay attention to time change zones when the time changes - some need to be manually set.
Athanotify is a good one to start with. https://play.google.com/store/apps/details?id=com.athanotify It works best on older phones but you can see what I mean.
athanotify (for android)
I always use athanotify.
There is an app on Play store Athanotify. It works perfect with Andriod wear for notifications.
https://play.google.com/store/apps/details?id=com.athanotify&hl=en