I've got a 16GB microSD card that I primarily use in my phone for local music playback. It's about half full - I really only keep my most recent music picks and a workout playlist on it, and stream everything else.

This MicroSD worked perfectly straight out of the box in my Samsung Galaxy Note 10.1! The official Samsung website says it only supports 32GB microSD, but others on the internet say you can use the 64GB if you format it properly. I didn't need to do any formatting and the card works perfectly!

Here is the FoneArena review of the SanDisk 64GB microSDXC memory card that was launched recently in India . SanDisk doesn't mention which class it belongs to, but after further investigation on some sites it is clear that it is a Class 6 Memory card. SanDisk promises read speeds up to 30 MB/sec.