I got a pair of them, too. I use them mainly for movie storage for my Nexus 7. You can use a 64GB card, but you (usually) have to reformat it as FAT32. The 64GB cards come formatted with exFAT, which isn't widely supported by Android devices.
What about battery drain with this adapter?
No idea. I haven't noticed much of a difference. What are you trying to do? The main reason to use an adapter like this seems to be to play videos stored on a microSD card. I would strongly expect that the screen and CPU/GPU would be dominating the power usage in that case.
Originally Posted by marksibert
I've got one, but it hasn't worked since I upgraded to KitKat. Stickmount doesn't seem to work for me, either. Does anyone have this working with KitKat? What's the trick?
Unfortunately, the 4.4 update removed USB-OTG support. You can't mount USB sticks anymore (unless you root and install StickMount). However, you could use a third party application like Total Commander with the USB Stick plugin. You still can't mount the card, but you can access files through the Total Commander app.
FYI. I got USB OTG support working on my Droid Maxx. I'm rooted, but otherwise haven't done anything out of the ordinary to the phone. I don't think you have to be rooted to get it to work, but I have no way to verify that myself.
Anyway, the instructions are over in the Moto-X forum, and they work fine for the Maxx.
In addition the obvious proficiency with graphics, creating agood Android theme … more
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