I asked this question a long time ago and discovered that its better to install to the device performancewise, your phone reads the main storage first and then the card causing some unstability or errors in time if installed there, i got everything installed to the device and havent had any problems, but then again i agree with the preveous post, if you want to economize storage memory you can install secondary programs such as games to the card. but programs installed to the device run more stable than to the card.

hope this helps