It is unclear (to me, at least) from the documentation whether Activity.onStop is guaranteed to be called. There are two places with seemingly contradictory information.
Is
Activity.onStop()guaranteed to be called (API 11 +)
Yes, it is guaranteed to be called on post-Honeycomb devices (API 11 +)
Source 1: Video tutorial on Activity life cycle - taught by Google developer advocate
Source 2: https://developer.android.com/reference/android/app/Activity.html#ActivityLifecycle
Source 3: AndroidLifeCycle article on www.vogella.com