Originally Posted by kristalsoldier
Also, is it true that when connected to a PC the Sony phones are not recognised as USB devices?
From version 4.0 Ice Cream Sandwich (well, started with the tablet-only 3.0 Honeycomb, really), Android uses the Media Transfer Protocol (MTP) instead of regular USB Mass Storage Class (MSC). I don't have the Xperia U but on my Xperia Acro S, I have the option to use either MTP or MSC. In MSC mode, only the microSD card is accessible. Since the Xperia U doesn't have a microSD slot, it probably only works in MTP mode.