Incredibly feature rich for the price.
I downloaded this app shortly after it was released and was blown away by the features and breadth of supported formats, despite some bugs in the 1.0. I contacted the author and was happy to see my questions answered quickly.
As of the 1.1, the database now has even more files than before from some of the most popular formats.
I do have some small complaints like the laggy world charts, but it is new as of 1.1 and will inevitably be reworked. It is not enough to detract from the basic usability however.
For a multiformat mod and game music player, it's unbeatable at a dollar.