Basil's System Monitor app should give a good idea of battery levels. That has a daemon that records a week's worth of levels in a database. I built it for x86 but the battery level wasn't working. Luckily, CODeRUS had given the correct battery device name in an issue, so it works now on my github. I suppose the Cell traffic output should be disabled and hidden on non-GSM devices too.

I've not pushed to openrepos before, but I'll give it a go.

Edit: I've uploaded it, and sent a PR to basil with the changes that should find the correct battery device on each device. If he publishes it himself then I'll remove it.

https://openrepos.net/content/abrans...tablet-edition