GNSS/GPS
@Flohack74 said I should post this here :)
gpsd configuration: postmarketOS/pmaports!494 (diffs) (one udev rule to symlink the usb interfaces to a nice name; a gpsd device hook script which calls atinout[1] to enable or disable the output from the modem, and some init script which tells gpsd about the device).
Then gpsd should just work (e.g. with cgps or gpsmon on the command line or any other application which talks to gpsd directly).
As far as I know QtLocation is used in Ubuntu Touch so https://github.com/jmechnich/qtposition_gpsd can be installed (build with qmake, install built .so as e.g. /usr/lib/qt5/plugins/position/libqtposition_gpsd.so
(basically in the folder where libqtposition_geoclue2.so
lives at).
And then applications using QtLocation (e.g. satelliteinfo from the QtLocation examples as shown in the picture above) just work
[1] A dependency which is probably not packaged yet in Ubuntu, v0.9.1 can be pulled from sourceforge, don't forget to include https://github.com/beralt/atinout/commit/133bf25ce0b7a73847aa9f84bb7d89ea7df5bbb3 (and potentially https://github.com/beralt/atinout/commit/ca2e04f8b069d269172f0d55d3716a809537f696)