I'm having a very silly issue with the Android app. Hard coded in to the app (with no option to turn it off) is that it will only run when the phone has the charger plugged in. When I started running this the phone was at about 90% charge and it ran great as it went up to 100%. I have found that there is an option to keep tasks running while the screen is on and so can now see what it is doing.

My phone must be turning off the charging circuits when fully charged (for obvious reasons), but must also be saying "I'm not being charged" so the app suspends all the tasks. A few seconds later everything else on the phone (screen and other apps) uses a bit of the battery so the phone decides to start charging again. The app then picks that it is charging again and resumes all the tasks.

I assume that the displayed battery percentage is rounded to integers and that what the app sees is probably 99.999... so to my mind, rather than "only run when charging", in addition to the minimum battery (defaults to 90%), it should say "always run if battery > 99.0%". OK it would mean it would run on battery for a short while when unplugged from fully charged, but only the short time it took to use 1% of the battery (which with the amount of CPU it uses wouldn't be long).