I'd like to know this too
I've looked through the forums but don't seem to find a definite answer. I have a rooted (with towelroot) Xperia V, with latest official nordic update.
So as we know, the big problem with Xperia V is that no matter how big external SD card you have, you cannot install APK's on it, making you run out of space real quick. The 2GB internal extended memory shows as "SD Card" to most software and the installers. Also, many apps don't let you explicitly define the location for file saves, so the 2GB will be used for caching etc on many occasions. Moving software to "SD card" in app settings as you would normally do on Android actually just moves between the internal extended memory and phone memory, but not the actual SD card.
I want to install my APK's on the SD card, and only keep minimum stuff on the internal 2GB. How do I do this? Can I make the phone not use the 2GB and instead use the 32 gig SD card I have in my phone? Can I somehow move the already installed apps to the actual SD card as well, or do I have to reinstall them?