I still use my Garmin Geko even now. Useful as a basic device recording a track I can geocode photos with, and runs for days on two AAA batteries. In a pinch you can reverse a track and go back the way you came too 😅
That’s such a good idea. My camera has to pair with my phone to get GPS readout and it’s a nightmare app. Going to look into this
Openstreetmap has a load of tools to help with this, as we used to use this technique for surveying.
For example, JOSM can geolocate photos against a GPX file, and display them over your map.