If you run the CPU in a loop at 100% load, it lasts around 40m or so, per the video. Using it interrupted and allowing to sleep it would last much longer - wit

If you run the CPU in a loop at 100% load, it lasts around 40m or so, per the video. Using it interrupted and allowing to sleep it would last much longer - with the default firmware the screen is only on when the user taps the device button.