I have a non-rooted Onyx Boox C67ML Carta running stock Android 4.2.2.
Once installed, when I tried to run it, the whole device totally froze. See below for a picture of what it looks like.
When this device had frozen on me before, I had always been able to force a reboot by holding down the power button. That does not work in the current situation.
I carefully used a knife to take off the back cover to try and find the battery. The battery does not seem to be removable without physically breaking the device.
I suppose I could wait for the battery to run out. It was quite low when the incident occurred. It may actually be out already, and the device off, since e-ink screens may continue to display the last picture they showed when something goes wrong, even without power.
What should I do?