Windows Phone 8.1
Windows Runtime Component
Sometimes the answer is easier than expected.
Class Librarythat targets only Windows (Phone) 8.1
Class Librarywith the Background Task
Do most of the work in the
Class Library and only make calls from the Background task, this makes the BGT look cleaner. The nice thing about using a
Class Library is that you can use generics.
You will have 2 Background Tasks for your universal app