I've had the low battery thing work in 1.9.11 (I haven't yet tried 1.9.12) the low batter warning does not pop up in a window, when the battery is 10% or 5% the little battery symbol at the top of the menu will have the 5% or 10% label in the battery or right beside it (I can't remember). But it said it was 5% and then I turned the page and the battery died, I was of course at the dentist when this happened so I had nothing to do but stare at the X-ray of my tooth like a moth to a flame