Hold it either way. Turn the phone upright and the engravings and the screen's lettering turn to face you; the buttons stay exactly where they are, as they would on a camera. Shot upright, a frame is two tall pictures side by side; shot sideways, two wide ones stacked, first shot on top. The black divider between the two pictures is now drawn fresh for every frame, from measurements across a whole roll of real half-frame scans — never the same width twice. Fixed: photos taken with the phone upright came out upside down.

A new body. Double Half is now a camera you hold sideways: a screen, four exposure lights that count your shots, three buttons for focus, film and flash, and a proper shutter. Pictures are landscape now — what fills the screen is what you get — laid two to a frame the way half-frame film does it. Far focus now finds infinity on your phone rather than being pinned to the end of the lens.