Hi Kevin,
thanks for your feedback, everything you have pointed out are problems we have detected in the app and we are working to solve.
In order to be able to solve that type of problems we are planning a different approach of how we implement WebServices in Moodle and how we release new versions of the app.
I will make an announcement next week explaining it.
BTW: I think that one of the problems you are having is this one:
https://tracker.moodle.org/browse/MDL-45041
Regards