In reply to Removed UserJames Bartlett:
I use OruxMaps mostly, when out and about. I can plan routes anywhere with this, as the UI is very good. It also does track logging. Routes and tracks can be managed within the map, and it can open GPX files from anywhere within the accessible memory space of the device. It also does 3d draping to DEM data (I have SRTM for the entire UK).
I also use OS Mapping occasionally. It isn't a patch on the usability of OruxMaps, especially regarding route/GPX management; it only has a flat file storage, and does not support any folder structure or hierarchy. I can plan routes in the field.
I also run a Traccar server, which my phones can report to (using the Traccar Client app), and dedicated GPS/GPRS trackers can report their position via GPRS, for use with DofE groups. I can access the server remotely to monitor the position & progress of the groups (using the Traccar Manager app). This allows the creation of routes & geofences in the field, too. Traccar doesn't export as GPX, but I have a script to convert the Excel output it produces into GPX.
I don't upload my routes to any external services. I do process the GPX files for various purposes, to plot velocity, etc, using some custom scripts.