I have tried most of the caching apps, but this is the only one that I use - both caching and cache management.
Its features include live searches and the usual caching tools, but provides the ability to maintain multiple databases (groups) and to import, filter, edit, merge and export cache information. The transition between online and offline caching is seamless. I link to routing apps from each cache page (including Navigon, Here, and Pocket Earth). I have never seen a better display of each cache page.
I maintain groups of caches I might want to find when traveling, solved puzzles, and other criteria. Add to this, the ability to edit cache descriptions, change the coordinates, ignore caches internally, and do projections. If I want to use my handheld gpsr, I export the data from Geosphere to it.
Some reviews have blamed this app for limitations of the Groundspeak API. And you will need to install the language fix in the app to correct some problems with the display. The apps forums provide help and support, but Geosphere has always seemed simple, easy, and powerful to me.