I have the Galaxy Note 10.1 and I'm assuming your Tab has approximately the same set up. If you're wanting to install apps on the external card, you can't. Even app2sd apps won't work. You can write media to the external card easy enough, either through drag and drop from a PC or 3rd party apps that have a "save as" feature. Back ups can also be written to the sd card. Aside from all that, there are hacks floating around that will fool the device into thinking that the sdcard is the internal storage. I don't know if any are available for your tablet though. Hope this helps. Good luck!