AudioTag - AudioTag.info — is a free music-recognition service.
Mixed in Key - Mixed In Key is award-winning DJ software that gives you the #1 technique of the world's best...
Shazam - Shazam is a mobile app that recognizes music and TV around you.
Tunebat - A browser based song key and bpm database. Supplies compatible songs for harmonic mixing.
ACRCloud - Automatic Content Recognition (ACR) cloud services for Audio Recognition ( identify music, ads ), Broadcast Monitoring, Second Screen, Copyright Protection.
KeyFinder - Key estimation software for DJs