Other than additional storage space, the main additional feature provided with an annual fee by Apple (and formerly ) was "scan-and-match", which examined music files on a computer and added a copy of matched tracks to the user's music locker without having to upload the files. Previously, there were three large services- Amazon Music, Apple's iTunes Match, and Google Play Music -each incorporating an online music store (see comparison), with purchased songs from the associated music store not counting toward storage limits. This is a comparison of online music storage services (Cloud Music Services), Internet services that allow uploads of personally owned or licensed music to the cloud for listening on multiple devices.