Geocaching, for those that don't know, is an outdoors sporting activity / treasure hunt in which participant use a GPS to navigate to a given set of co-ordinates, in order to find a geocache (cache). The geocache is usually a container, inside which you'll find a number of items including a log book that you can sign with a date and name to record your visit.
The Geocaching Live app has been developed by Groundspeak Inc. the company behind Geocaching.com, the biggest geocaching community on the web, which has been largely responsible for popularising geocaching and providing a list of geocache locations. To use the app you'll need a Geocaching.com user account (you can sign up from the app if you don't already have one).
The homepage of the app shows information about your profile and your current location. From the toolbar you can access a list of nearby caches or search for caches based on an address, postcode, GC code or trackable code. In both cases a list of caches is generated, with summary information about their location, level of difficulty and cache type shown. Lists can be viewed in map view (with either Bing Maps or OpenStreetMap used for the underlying map), saved for offline use and sorted (by distance, name, type, difficulty and terrain).
Each cache has its own panorama with a summary page (title, description, location etc.), logs (messages left my people who have visited the cache), notes (extra information about the cache), trackables (items in a cache that you're encouraged to move to another cache). From the toolbar you can access info (description of the cache), photos, hint (tip about where to find cache) and navigate (map view). In the map view you can add way points, which is helpful when solving multi or mystery caches. From the extended menu you can access a compass view (useful for the last few hundred metres), create a log entry (to record your visit) and save a cache for later offline use.
Saving a cache for offline useful is very handy as more remote cache locations may have slow data connections or no mobile signal at all. Caches that have been saved for later use can be accessed from the backpack option in the home panorama's menu.
The app is available for other mobile platforms and has been ported to Windows Phone, but a reasonable effort has gone into making Geocaching Live feel like a Metro app. There are also some exclusive Windows Phone 7.5 features including a Live Tile that automatically updates to show the nearest geocache to your current locations and the ability to share caches to social networks. All in all it's a very impressive app and is the perfect companion for your next geocaching adventure!
It is worth noting that if you're planning to download the full details of more than 3 caches a day, you will need a premium subscription to Geocaching.com, which costs $30 a year. However, there are no other restrictions and the 3-a-day limit should be fine for casual users or those getting started with geocaching for the first time.