iPhone app Bump is a way to share contact information (like an electronic business card), but now the app lets you share music too. The most recent Bump app update lets users select songs from their iTunes collection to share with friends, just by bumping their phones together. Recipients of shared tracks can give the song a listen, and it automatically links up to a relevant YouTube clip, with ability to preview and purchase the track from iTunes. Bump already supports event and photo exchanges, and can also be used to set up new connections on Facebook, Twitter and LinkedIn just by bumping phones together. PayPal even lets you transfer funds using Bump.