I'm pretty much buckled up and ready for my holiday in South America, although there's still something I haven't got resolved yet, and that's geotagging of my images I'll be taking during my holiday.
I have been looking at different solutions, which are standalone units and smartphone applications. But honestly I don't have experience with this and how good the different software are when tagging a few hundred of images or more.
What do people use and do you find it robust?
I don't know about you but my smartphone just doesn't have the battery life to make this work. I therefore use a standalone GPS device made by Holux. It's Bluetooth-capable and transmits the GPS coordinates to a Foolography Unleashed device attached to my camera. The Holux device runs the whole day on a single charge, and with this setup all my images are GPS-tagged in-camera.
You can also use the Holux device "offline" because it also records a track which can be applied to the images when downloading them from the camera (the clock on the camera needs to be more or less correct, but that's not so hard).
EDIT: I forgot to mention that the Unleashed also works OK indoors, after a fashion; if the GPS signal is lost (becasue e.g. you went indoors) it continues to serve the saved position (but an up-to-date time) for 30 minutes. I like this feature. I assume though that if you're geotagging your images from a GPS track, you get pretty much the same functionality by doing that.
MapAPic is an iPhone app that lets you geotag your locations, and create a searchable list of locations, along with multiple pictures, tags, etc. I think it does exactly what you need.
Disclaimer: I am the author of the app :)
You don't say what camera you have. Some cameras have a port that among other things can be connected to a GPS. For example, the Nikon D3S has such a port and Nikon makes a GPS accessory for it. Other companies do too. In fact I use a third party GPS. These GPS units have a foot so that you can mount it on the flash hot shoe if you want. That's what I do since I rarely use flash.
Once the GPS has acquired satellites, all pictures are automatically goetagged in the EXIF data. A nice side feature of the D3S at least, is that the GPS also automatically sets the camera clock.
So see what might already be available for your camera, and don't assume the camera manufacturer's GPS accessory is the only choice either.
I assume you want a GPS that records your position all the time and let you sync with your pictures later - if that's the case I would go with a standalone unit.
On my iPhone turning on the GPS drains the battery pretty fast (I think the GPS will completely drain a full battery in less than 5 hours).
When driving this is solvable with a car charger but if you plan to go on an hike - or otherwise be unable to charge you phone for over a few hours - than using your phone is just not practical.
Also, if your standalone GPS's battery runs out you just lose automatic geo-tagging, if your phone battery runs out you lose access to all your apps - and obviously you also can't call anyone.
I use an app called Geotag Photos on my iPhone, and an Android version is available. One of the things that I really like about it is that it gives me an easy way to help manage battery life: I can set the interval of location recording. That is, I can let it record my location continuously (and drain my battery), or I can choose from many intervals all the way up to once an hour. I find that when walking, in most scenarios setting it to every 10 minutes provides plenty of datapoints for me, and the battery still has a bit of a charge at the end of the day after some phone and other app use.
I use my smartphone (android) and the app GPSLogger. It is fairly easy to use and you can save the tracks as gpx-files.
I create them on a daily basis and use Lightroom’s Map module to add the coordinates to my photos.
I uses “satellite time” in GPSLogger, but for my next trip, I’ll change this to “System Time” to avoid recalculations of UTC to whatever …
I carry an Android Nexus S, but use an AMOD GPS logger. Its small fairly inexpensive, and easy to use. Google for "Amod AGL3080 GPS Data Logger" and you'll find lots of stores that carry it.
Aperture 3.x would load up the file and apply them to the photos with zero effort. I'll find out how well Lightroom 4 does it in a week or so.
If you are a Google user and have a smartphone, all you need to do is enable Latitude detailed logging on your phone, and then use a 3rd party application to modify all your photos and insert the geotag information at any time afterwards.
There is such a free app that I developed and put on the Apple Appstore (for Mac Computer Apps), but it might expire soon. I'll publish it in the future if there is any interest. (For free again)
It's called Longitude
It depends on how easy you can load your smartphone, because using GPS is taxing on the battery (although a cleverly written app can make a huge difference). See my other comment: https://photo.stackexchange.com/a/26333/10367
