Welcome to Android Central! The way Android works, you have to install your apps in the Internal Storage. Some devices allow you to "Move to SD Card," but this sometimes means a separate portion of the Internal Storage, and not the actual microSD card that you insert. But even when you can move an app to an SD card, it's only a portion of it that you can move, so you don't really save that much space.
See these guides:
http://forums.androidcentral.com/gen...id-2014-a.html http://forums.androidcentral.com/amb...-warnings.html