I use Geotag Photos Pro 2. This logs your position on your smartphone. You then match the log with the times of the photos as shown in the Exif file. The advantage of this system is that it is cheap, simple and works with multiple cameras at the same time with no need to buy a dongle for the camera or worry about the connection with the camera, because there is none. Also, you can download a log of a trip as a whole and see where you went on a map, whether or not you were taking photos at the time. There are other similar apps available.
The only disadvantages for mr are that you have to synchronise the camera clock with your smartphone clock (but the program has the facility to make an offset adjustment) and that the photos are only geotagged once you are on your computer. And you have to remember to open the app to start the logging (
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A problem I had with the Foolography device was that it was very hard to find a receiver to store the data which was compatible with Apple Macs. That situation may have changed.
The other problem I had was self generated. I accidentally lost the Foolography device at Å in Lofoten (Birna knows that place well). Amazingly, I went back and found it on a gravel path. It had split into two parts. I glued them together and it worked as well as when it was new.