Been meaning to try it. I have plugged a flash drive and a CF reader in with no issues. The device can't seem to read NTFS though. Soon I will be trying a GPT partitioned drive formatted as exFAT and FAT32. I haven't had my OTG cable long so I haven't had allot of time to experiment. Wanted to plug into my USB hub and see how many drives I can mount as well.
Samsung Galaxy Note 3 (SM-N900T) (Radio-NB4) 4.4.2 Rom (Stock NB4/Root/Deodex)
Samsung Galaxy Note 8 (GT-N5100) (Radio-MJ2) 4.2.2 Rom (CivZ-FLEX-BEAM-REV3.6.2)
Samsung Galaxy Tab 2-10" (SGH-i497) (Radio-MF2) 4.1.2 Stock