> "Treating things like this as independent modules opens the door to add some really neat things without compromising the simplicity of the screen or, hopefully, the stability of the app."
I like the "develop it in stages" approach. With this as a design philosophy, the sky is the limit with the number of and sophistication of features. How much better this is than what I've seen with, for instance, Anywhere Map. Their products come loaded with advertised features many of which, out of the box, do not work. The company's motto is "coming soon," regarding features which are advertised as currently available and working. It took two years for AWM to fix the bugs in the ATC following its release and some of its advertised features still don't work. They've done the same thing with the Quadra, releasing it with the software half-baked and loaded with bugs. Their Quadra forum is full of complaints from unhappy customers.
A gradual development of features such as with the iFly is a far more sensible approach, seems to me.