Spotisquare is a mobile mash-up and Foursquare client that lets its users attach music to specific Foursquare venues. After checking in through m.spotisquare.com, users can look for music attached to the venue. If music exists, users can stream the playlist via the Spotify mobile app. If no music exists, users can attach a song or playlist that helps other users to experience that venue via the attached music.
In order to use Spotisquare, users need both a Foursquare account and a Spotify account. In addition, the Spotify account must be a Premium account to work on mobile phones and songs/playlists can only be added via a laptop computer.
While Spotisquare is currently limited (no mobile app and adding of songs/playlists only by computer), it clearly represents a step towards a future in which music is used (like other data – check-ins, tweets, etc.) to mash-up and socialize online and offline experiences via the mobile phone.