I've never tried anything like that but what little I know I think you need to be rooted and use an app called StickMount which requires root to work. And I think you will need a custom kernel to have NTFS and exFAT support. I use the ElementalX kernel which has NTFS and exFAT support but most if not all custom kernels probably have that support also. Transfer speed probably wouldn't be that great because I think the bootleneck would be the speed class of the memory card. I would be surprised to see speeds higher than 20-30 MB/s. Hopefully someone more knowledgeable in doing what your trying to do will jump in here and enlighten both of us!
yes it can be done I use flash drives all the time. I also hook up my seagate 1tb backup to my nexus 5&7. you will only need an otg cable or adapter. a hub if you intend to use a keyboard and mouse. ive never done that but have heard of it being done. im runnig cyanogen on these devices however ive used usb card readers and a 64 gb 3.0 flash on my m8 full stock. 4.4 will accept external usb ive read. just try it you"ll like it
