Works great for the month I have had it in my Galaxy S3.  I purchased this to go in my Samsung Galaxy S 3 and was super excited I didn't need to buck up more money for the 32GB phone.  Well *dumb* me did not know the the SG3 does not allow apps to be moved to an external SD card.  I thouhgt I had researched everything but I missed that.  The card works fin and I can store umpteen thousand pictures not that I have figured out how and I might even be able to figure out how to put a movie onto it but what a waste of a GREAT SD card.Pro: Top of the line cardCon: SSG3 and most new smartphones won't allow apps to sd even with the micro sd card option on the phone