- RGN file support
- convert between RGN and GCD
- Express-like updater
- should be text interface or ncurses
- detect Garmin MTP devices or /GARMIN directory in mounted roots
- MTP support: https://github.com/wangjiezhe/pymtp
- fetch GarminDevice.xml
- upload to Express, list returned files
- ask user, then download files and push to device
- maybe: support for additional downloads (languages, icons, etc.)
- maybe: support for running under Windows (although there you have the real Express)