AT&T offers 5GB of free cloud storage to Android and iOS users with AT&T Locker3
Should you need more space, you can get 30GB for $3.99 per month, or 100GB for $9.99 per month. AT&T’s 25GB tier pricing is a little more than Google Drive, iCloud and Box. The 100GB plan is on par with Dropbox and SpiderOak. One handy differentiator is that AT&T Locker does not currently have a file size restriction unlike Dropbox, Google Drive, iCloud and Box.
This service may have appeal because as users upgrade their devices, and plans, they can keep their media on the carrier’s own cloud without any worries. While these other services are well established and competitive, there is that small segment of users that may not want to use a non-carrier solution. So, while AT&T Locker may not be a runaway success, it will serve that niche just fine.
What is also nice is that the service and app is available for users of the iPhone 3GS or newer, and Android versions 2.1 and up. Of course, uploading and downloading all your goodies will chew-up data, so you will want to monitor your usage accordingly.
source: AT&T (1, 2)