I noticed another thread here on how to use your external SD card for apps only me being a noob it was far too complicated. I managed to find this video tho and tried it on my device and it works perfectly. You need a rooted device with Busybox and Script Manager to do this and then you will need to download this script and use Script manager to run this script at startup which basically swaps the internal and SD memory around so your device thinks your SD card is SDcard0. Video explains everything quite nicely.
There are other options out there that work too such as an app called Directory Bind, but this is way easier and much more reliable. With directory bind i was having huge problems trying to access the SD card or internal memory when plugged into my PC. Hope this helps.