Man, I hate to throw cold water on this, but I think the issue is with the consistent unreliability of Canon Connect software. (And clunky Canon software in general.) It is totally unreliable, no matter what camera I've used. With some of my cameras, I've NEVER gotten it to connect. R5? G1-X MKIII? Forget it! Take the R5. I spent 45" on the phone with the factory rep a while back, because the R5 simple would not connect with my iPhone. We went through every conceivable connection trick, checked everything. Finally he told me the R5 was broken and I should send it in. I did so. Spent $XXX dollars. Tech called me and said they could find nothing wrong with it, particular with the BlueTooth function which was to spec, and were sending it back. (Side note, I got my money back after I complained about this exercise in futility.) I called Canon again now that
for sure everything was working, and after going through everything again, the tech just gave up and said, "I have no idea why it won't connect." How's that for reliability? And that's on the R5! I have had some success with the G1-X MKIII, but as was pointed out by "P-visie" above, Canon Connect needs all things connected all the time, i.e., no "going to sleep" by either the camera or the phone, otherwise, no GPS... That means you're concentrating on shooting and then, afterwards, find out that there was no GPS data that you thought you had! How frustrating (to use a mild term) is that?!?!?
I use the GPS all the time with the 5D MKIII and R5 via the Canon GP-E2. It just works and works well. I usually bring the G1-X MKIII (and before that the MKII) as a back up/movie/wider angle lens, and there of course is that GPS data problem. Here's how I've handled it... whether it's a solution for you, I cannot say, and am just offering up what I've done and works for me, given Canon's long time lousy, unreliable software issues.
Assumption: Trying to get the camera and iPhone to sync AND trying to concentrate on taking good images is mutually exclusive. ^%!@#$! around with the iPhone-camera every time I want to take a photo is frustrating, time consuming, and causes me to miss shots. Therefore I don't. It's a waste of my valuable time. Therefore:
Scenarios:
1) If I'm in one location for any given time, I'll just take a shot on my iPhone for the GPS data and add it to all the photos later. (More on that later.)
2) If I'm in one location for any given time, and If I'm using the G1-X as a backup (as described above) to my R5 or 5D with the GP-E2 unit, I'll just use the GPS data from the images from the R5/5D.
3) If I'm moving around a lot, I'll take a shot on my iPhone for each series, and match the GPS to each photo later. A bit time consuming but reasonably effective.
Now, key to all this is using
GraphicConverter. If you don't know what it is, it's an
amazing program, fairly easy to use, and it has been called the "Swiss Army Knife of Image Management." (Unfortunately, there is no Windows equivalent that I know of.) It was the program originally bundled with the Mac before Apple developed "Photos", which oddly can't really do much of anything that GraphicConverter can do. (While GraphicConverter has a lot of the same basic Photoshop functions, that's not really the major use of the program. You can read up on it on your own.) Anyway, it'll copy/paste GPS data from one image to another (or in batches, whatever) and allow you to "tweak" locations easily (via a pin on a map, so "ronbyram's" issue is easily resolved.) I will usually just dump all my images into a folder for the day, sort by EXIF date data, number and title all the images in a few seconds, and then through the browser, check visually for any photo that doesn't have a GPS icon, and copy and paste) GPS data into (and adjust if necessary) any image.
So, this allows me to get around all that unreliable, clunky "Canon Connect" issues, and just stick to shooting, taking an iPhone image for inputting the GPS data later if I have to, or just knowing I can quickly easily input the data later from images with the GP-E2 data.
Anyway, all I'm saying is that's what works for
me and offer it up as food for thought and a possible alternative to frustrations and the unreliability/inability of Canon Connect. I've been doing this for many many years and it works very quickly and very well for me. Good luck to you!