There are two ways to record a track for geo-tagging photos or other uses. One is to use a smartphone with a GPS app: I use an iPhone 5 with an app called Motion-X GPS. The other is to use a GPS designed for back-country use: I have a 13-year old Garmin unit.
+ I’m going to be carrying this device anyway
+ There are a variety of GPS apps and map packages to choose from
+ It is easy to communicate geo-location information to other apps and other platforms, such as I do with my MacBook.
– A more fragile device
– The geo-location and map-downlaod technologies (GPS, data service , WiFi) can run through the battery in an afternoon*
– Maps are selectively downloaded as needed, so I have to remember to force a download for an area without data service before I get there.
+ A more rugged device
+ Batteries last a long time and are replaceable in the field
+ Maps are always available
– One more device to purchase and to carry
– Transferring geo-info to/from other devices can be a hassle, particularly if you use a Mac. (I can’t use my old Garmin directly with OS X.)
* I plan to carry an external battery pack for my iPhone during some late-June hiking in the western US to see how this works.