This is just to say, a little belatedly,
THANK YOU
We watched the whole lot over the course of last month. I have not got around to a serious write-up here as yet, though the series very much deserves it. We just might have to watch them all again. How soon do you need them back?
As far as I can tell, the battery life on touch-screens is generally of that kind of level. My understanding from reviews is that the iPhone (and other capacitive screen phones) are similar in this respect.