With ICS, users will notice quite a bit of changes. One subtle change present on most devices is that UMS (USB Mass Storage) has been removed. In its place, users will find that their devices connect to computers via MTP (Media Transfer Protocol).
There are advantages to both protocols, but for most users it comes down to preference and compatibility. One major drawback is that not every operating system is compatible with MTP natively. And if you’re not keen on using third-party software to transfer data, this can become pretty messy. For Samsung Galaxy S III I9300 users, SGS3 Easy UMS aims to solve this issue.
The application is developed by XDA Forum Member Kopfgeldjaeger, and makes the SD card on the Galaxy S III a USB Mass Storage device for users who wish to get around the restrictions of MTP.
The app is simple to use. Users simply install the apk, open it, and toggle UMS on or off. It has only been tested on the International Galaxy S III so far, but it could very well be compatible with other devices with similar configurations.
For additional information, head over to the application thread._________