Hardware back button does a "semi-exit", not a real exit, but not a regular background either

ionic v2 rc4
Android 6.0

3 scenarios here:

#1
If I use the hardware back button, it goes back to the home screen. But it is still showing as a running app in the system, then when I reopen the app, it has a black/blank splashscreen for a few seconds, then it starts up.

#2
If I actually kill the app, and then start it, the splashscreen shows properly.

#3
If I just go to the homescreen while the app is running, and then go to the app again, it immediately comes back just like I left it.

So, it seems that using the back button to exit doesn’t really exit, but it doesn’t simply background the app, either. Because it takes a few seconds for it to startup again, but it shows a black screen for those few seconds instead of a splashscreen, hence the “semi-exit” term that I used in the title.

Any ideas here?