System Update
New firmware releases are published on github. They are listed here. If there is a new release, the app will notify it's availability.
Select one of the releases to install. In general it is advised to install the most recent version.
Firmware can also be uploaded manually. Select choose file, Press Upload if asked for Are you sure you want to overwrite the existing firmware with a new one?. Wait until the connection gets lost and is re-established. Then the new firmare is installed.