From postmarketOS

Device Notes
Apple iPhone 4s (apple-iphone4s) Unable to activate
Apple iPhone 7/7+ (apple-iphone7) Untested, iCloud locked
Google Pixel 3(google-blueline) Untested
Microsoft Surface RT (microsoft-surface-rt) Currently running PostmarketOS!!!
Nintendo 3DS (nintendo-ctr) Untested
Raspberry Pi 3 (raspberry-pi3) Untested
Raspberry_Pi_4_(raspberry-pi4)} Untested
Samsung Galaxy Tab A 2016 (SM-T580) Unable to install due to heimdall not flashing TWRP