iTunes Match gives customers access to their music libraries from any iOS device or authenticated desktop computer. The service uses the magic of iCloud to ‘match’ and upload tracks from an iTunes account so that songs can be played and downloaded multiple times on multiple devices.
While Apple has offered some documentation on the innards of iTunes Match, aspects of the service remain unaddressed. For those wondering, one iTunes Match account can be used with a maximum of 10 devices. You can manage your registered devices and iTunes Match subscription inside your iTunes account settings.
When you login with your iTunes Match account/Apple ID on a desktop computer or iOS device, you take one spot on your list of 10 allowable logins.
To access this list and manage your iTunes Match subscription, go to your account settings in the iTunes Store. On your general Account Information page, you’ll see a new section called “iTunes in the Cloud” under your Apple ID Summary.
In your iTunes in the Cloud settings you can do two things: manage your registered devices, and turn your subscription auto-renewal on and off.
From the Manage Devices window you can see a list of devices that are logged into your Apple ID and remove each device manually. The date that you added the device is also displayed for reference.
As Apple notes, it takes 90 days to totally remove a device from your list of authenticated devices, so don’t expect to see an updated list based on the changes you made yesterday.
iTunes Match is set to automatically renew your $25/year subscription exactly a year after you purchased the service. You can turn off auto-renew under the iTunes in the Cloud section of your iTunes account settings.
Don’t forget that you can deauthorize a computer in the iTunes Store settings drop down menu. iTunes Match can be disabled on an iOS device in the Settings app under the Music section.