Your iPhone tags photos with all sorts of information: your location, the time and date the photo was taken, even exposure information. This tagging function can be turned on or off under Privacy > Location Services in your iPhone settings. Surprisingly, you can't see the tag information on the iPhone itself, but it is available in iPhoto and other applications on a Mac or PC.
Pic Navi (free, ad supported) makes it easy to browse the photos on your iDevice and see each photo with a date and time displayed. Tapping the compass button in the app displays a map of the location where the photo was taken and tapping the pin on the map provides directions to get back to that spot.
Moving between photos is easy. Just swipe left or right and the metadata is displayed automatically.
Pic Navi for iOS
Pic Navi worked very well. An in-app purchase for US$2.99 gets you the Pro version, which allows you to share the locations by email, Twiiter or Facebook. With the Pro version, you're also allowed to change the font and color of the time and date stamp, and the ads are removed. I was satisfied with the free version and did not find the ads to be intrusive.
There are some other apps with similar features, like Photo Investigator (free with in-app purchases), but I like the ease of use of Pic Navi.
Pic Navi is a universal app, and it requires iOS 7 or later. It provides a function Apple doesn't on the iPhone, and many photographers will find it useful.