Ok. I'm gonna expand. It's a thread. Bear with. We have a client app. It has a tabbed interface. We got the following feedback from a customer: "App is hard to navigate. Wouldn't let me go from <tab4> back to the <tab3> page without it shutting down". And so begun a (1/n) ..minor voyage of discovery.
I started with our Android guy who wrote it. Straight off the bat he said "There's nothing on the back stack, so pressing back is instructing the phone to go back from where it came" (i.e. the home screen). (2/n)