Packrat is a media collection manager application for Android. You can use it to add books, CDs, games, movies, etc. to your collection by scanning their barcodes and organizing them onto shelves. You can let Packrat organize your items into smart shelves, or manually stack items onto shelves of your own creation. You can also track items you don't have yet on a "wishlist" shelf.
fretscpp is strongly inspired by the original FoF, reusing artwork to a large extent, with the source code rewritten from scratch. C++ instead of python should improve performance and allow easier support for features like whammy. It is playable, but some non-critical features are still missing.