A:Answer It affects the performance of app running on it. You are talking size of 64, 256 then you are talkin ROM of phone. which has very high speed of reading and writing dataspeed.
if you need memory as secondary storage, then you should only get memory cards.
If you are very fond of keep video recording and want to use in memory card, then
you have to put atleast class 10 level memory card then it may work fine and as much as fast phone rom slightly.