CheckinDJ is a crowdsourced jukebox that arranges a venue’s music playlist to match the overall taste of its current patrons. Users register online or via an app, and enter their favorite music genres. Once at a participating venue, they use an NFC-enabled device to check-in. The playlist at the venue automatically adjusts to reflect their taste. Individuals can earn influence points by syncing the app with their social networks, and by checking in with groups of friends. The platform was developed by UK-based Mobile Radicals.