I've been developed apps for iOS for sometime and find that there are many repeating tasks. So I want to write base classes that the upcoming projects will subclass, so that it will cost less time and more easily to track code across projects. The most concerned are
Write good base model class that has many strategies (Core Data, Archiving, ...). This model class also has some JSON-to-property converting techniques like Mantle so that model on device and on server are the same
Write good base networking class (mostly with AFNetworking)
Write good base ViewController class. I see some repetitive tasks : avoiding keyboard with ScrollView, logging, crash tracking, loading views from Nibs, ...
Find and use some other good categories for UIView, UINib, Autolayout, ...
These are just my concerns. It may seems a vague topic and I don't ask for how to use libraries or how to make reusable components.
I just want to ask about experience for making these kinds of base classes and where I can learn from