This app is a good start but it only finds GPS and exposure data on pictures in the camera roll album.
If you look at any pictures taken with your iPhone 4 camera and have moved them to a different album it will not pick up the GPS or exposure data. Yet the GPS data is there as it shows up for the picture in the places option of the iPhone photo albums. Next to the date and time location info for a given picture is the most important feature I wanted.
If Apple had better product management these features would all ready be included in the iPhone app.
Craig Edland about Lab, v1.1