>>17269970(me)as for how to use it, shutter button to take photos/turn on device, number on screen defaults to number of pictures left.
mode button (next to viewfinder) changes menu item (press it multiple times to switch between items), leave it alone leaves menu, shutter button toggles item
as for what each menu item does, i've since forgotten, but i do remember one switches compression mode (so it can store 72pics instead of 26, i never did know how it did that since it was still .bmp, but they looked pretty similar)
i think it turns off automatically from non-use
also, you can remove the internal piezoelectric speaker to stop it from making noise if you like