We love Easter eggs in games and software, and Marshmallow’s is a particularly good one – if you like that sort of thing…
Head into your device’s Settings by dragging down the top bar and then tapping the cog. Scroll all the way down to About phone and tap on its submenu.
Find the Build number menu and tap it several times. This should take you back to the homescreen and a big marshmallow should slowly appear on the screen.
Tap on the marshmallow several times and then press and hold in the middle of the circle. You will now be able to play a ridiculously difficult game of Flappy Android.