My gf just got an iPad mini 4 (iOS 9.3). She also has an MBA (El cap 10.11.3). To move files between them I used airdrop. Very smooth and easy. I tried the same thing with my rMB (EL cap 10.11.4) but the mini is not recognized. Same thing other way around. The mini does not detect my rMB. Anyone else having this issue with their rMB? Or better: solution to this problem? FWIW: I have also this issue with my HDD and usb-C flash not detected by the rMB every now and then. Both work flawlessly on her MBA.