OnApplicationQuit, Debug.Log, Application size

First post on the android section. Be gentle.
Some basic questions that I don’t want to start separate posts for below.
Thanks!

Say I am playing my game. Then I hit the home button. Then I open my game again, it has been saved but not by me but by the OS. i.e. the second time I enter, it is not really starting, (loading scenes and Awake) but is exactly where I left off. Pretty neat. However if I don’t play it for a while and maybe play another game, or power off the phone, and then I open it again, my progress is lost.

I am guessing OnApplicationQuit is not being called when the user presses the home button? (still figuring out how to debug)
Is there some other function that is being called at this event, so I can save the game when the user hits home?
How do I get debug logs nowadays?
I found this 1 year old thread which I will follow, if there isn’t a easier way.
Finally, what would be the app size on the android market? Would this be the .apk file size? (Don’t want to wait until I publish to find out).

Thank you!

From this thread looks like OnApplicationPause() is what I should be doing. Would be nice to mention explicitly that OnApplicationPause is called when the user presses the home button in the documentation.