When the phone is "off" but showing the charging animation, it's actually booted and the animation is a program it's running. There used to be a hack, I don't k

When the phone is "off" but showing the charging animation, it's actually booted and the animation is a program it's running. There used to be a hack, I don't know if it works on modern Android, where you'd essentially edit the init scripts and tell it that the charging animation task should be the rest of the boot process, or your specific app of interest.