Software update

build_app.sh is used to create selfomat.update files. These files contain all self-o-mat binaries and dependencies and are signed for use with the updater running on official self-o-mat boxes. You typically don't need neither the script nor the update file.

The self-o-mat boxes have a built-in bootloader app called up-2-date which runs on boot. It shows a nice GUI, reads update files from SD card, verifies signatures and starts the photo booth app. It may not be suitable for a DIY solution.