I know this might be a bit controversial, but I thought I'd share my my experiences of geo-tagging with the A7Rii.
Ever since the release of the first DLSRs I've always wanted a 35mm Full Frame sized detector. I've just traded my Pentax kit in for a Sony A7Rii; I was looking at the A7Riii, but felt I couldn't justify the extra expense. The one thing that the Pentax body had was a built in GPS receiver that wasn't too heavy on the battery and always locked on to a signal pretty quick. It was excellent for geo-tagging photographs. I was a bit disappointed that Sony cameras didn't have built in GPS, but realised that there was a way round it.
(1) I started by using 'PlayMemories Mobile' on my Smart Phone and 'PlayMemories Home' on my MAC. This I found was using the Smart Phone as a remote. I found that a GPS log was recorded on the SD card in the camera and when the photographs where imported onto the MAC using 'PlayMemories Home' that the GPS data was saved in the Photographs metadata. Even though the Smart Phone was acting as a remote I could still use the camera for taking photographs. The disadvantage Geo-tagging this way was that the Camera view finder is disabled and the only option is to frae the subject using the rear view screen.
(2). I have already been using an app on the MAC called 'GPX Photo Tagger'. This allows photographs to be loaded, together with a captured GPX log, and providing the times and dates from the log match the times and dates on the photographs the photographs can be saved with the location data in the metafile. I found an app called 'GPS Tracker' to track me when I'm out and it can export a GPX file I can use. This isn't as neat and the first option, but at least I can use the camera view finder.
(3) The third option I haven't tried yet is to use some apps called 'GPS4CAM' for the MAC and 'GPS4CAM Pro' for the Smart Phone. This is basically the same the second option above, but involves taking a photographs of a bar code to match the photographs. I haven't looked too deeply into this as an option but the development of the desktop app has stopped and the next update to the MAC OS won't support 32-bit apps, only 64-bit, and I'm not sure which the desktop version is. I don't want to waste time if in a few months I can't use it.
All in all, I think the first option is the preferred route if I could use the camera view finder. Failing that the second option is the route I'm using until something better comes along.