LR Photo Geo-tagging.
I'm sure many of you use this already, but I only recently noticed this LR function.
If you use Strava (or other similar app) to log activities you can import the .gpx from the app into the LR Map Module and use it to Geo-Tagg any un-tagged photos taken on the walk/ride/run etc via the image Timestamp.
It's easier if your camera time matches local time on your phone (though you can shift the gpx time (or image timestamps) within LR, but it adds to the faff).
I'm not particularly into Geo-tagging everything, but will use this now. Worked well on some via ferrata we did in the summer.