If you are shooting in the wilderness, then consider a dedicated GPS unit. Garmin devices are great (map format aside). I used GPSmap 60Cx with Sirf Star III chipset, and it was reliable and precise even in narrow mountain valleys/gorges. Garmin doesn't advertise which chipsets they use anymore, but you can find this information from the third parties. I think a good chipset and battery life is what matters the most for outdoor use. Rugged case is the next. Devices from the more expensive series tend to have better chipsets than devices with similar or better features from the cheaper series (e.g. GPSmap is better than eTrex).
I didn't find GPS maps very useful (also for the lack of official maps for my region few years ago and no support of scanned geo-referenced maps until the very recent Garmin models). It consumes the battery when used actively, the screen is not large enough, and you still have to carry a paper map with you. So if I were buying a new GPS unit now, I'd not pay extra for the mapping features. If you want a lightweight, but rugged unit, consider also the Foretrex series, which is also a wrist GPS.
Smartphone-based GPS trackers do not work reliably where there is no cellular coverage. Also, spare batteries tend to be much more expensive than spare AA- (or AAA-) batteries of dedicated GPS units.
P.S. If you buy a Garmin unit, just don't use its
Save track feature, it makes tracks useless for geo-tagging. Otherwise any device is capable of writing a GPX-track today. And there are plenty of free software packages to geotag photos later without hassle (ExifTool included).