I got a shock yesterday when I glanced at my phone just before the morning service and realised that the battery charge had dropped down to 22%. I fairly frequently recharge my devices but find that I can normally keep them well above this level. I think the problem was, helping in the underground venue we use for the church youth club the night before, the phone had lost carrier signal and had not managed to re-establish a connection even though it was diverting extra power through the circuits involved.
I dropped the phone into “airplane” mode (all external communications off) and it managed to eke things out a bit further (I normally just turn the phone to silent to avoid the chance of a call disturbing the service). It is now charged up and back to health but, next time I venture out of signal range, I might try to drop into “airplane” mode earlier.