The issues with the previous version have been squashed. gps4cam is once again a great working app. Even though there was an issue with the last version no data was lost, the developer was very responsive to support his application with good communication via email. Good support is a mark of a good developer.
This application is very easy to use and doesnt require the user to go through complicated offset time/place syncing steps like some freeware apps out there. Ive tried them and although they work it is a big hassle compared to this app.
Im working on a photo project involving geotagging thousands of images Ive been shooting. I geotagged over 10K images using gps4cam. The geotagged images can be easily brought into Apples Aperture application to view the Google map where the photos have been shot. Geotagged data will later be incorporated into a GIS system.
The application does eat up your battery, especially if you have it set to one minute intervals and shake the iPhone to add more trackpoints. My older iPhone 3G ran down the battery shooting all day, my iPhone 4 worked more like a champ and still had power to spare. Battery usage is due to the plain fact that using the GPS constantly will draw more battery power with any app.
One feature I wish the app had was to just point to a folder and select all the photos in it, or perhaps have a Select All button. Since I would shoot up to a thousand images it would make it easier/faster to select the images.
Overall Id say this is the closest experience to having a GPS built into the camera itself.
Media Baron about gps4cam - Geotag Your Photos, v6.1.1