I think this is the way we have been writing app objects which have their own wrappers for switching to app frames. Also, putting this in `__init__` would mean that instantiating the class object will automatically switch to frame, which in case of incoming calls is fine and that's how it would be used most of the time. But we never know what kind of situation we may run into in the future where not having this in `__init__` may be ideal.