Sony Xperia S is also capable for USB OTG (USB On the Go) function like other Sony Mobiles like Xperia arc, Xperia arc S, Xperia ray and the new 2012 range of Xperia devices which currently is the Xperia S, Xperia P, Xperia U and the Xperia sola. The problem is not all USB OTG cable are working with these devices. Attach USB Flash Drive with your Xperia and it can read the images, can be used play a movie with music directly from USB Drive.
Tested and working after opening the ASTRO file manager the App will see its path is built-in storage space, this time according to the last row of the “up”, they can find a usbsisk the folder, this is the path to an external USB flash drive.
You can see in these videos:
Sony Xperia Phones Supports USB On-the-Go
Sony Xperia P USB Host Mode