If you pay attention, you will hear that the Mojo is better than the 12.9 iPad Pro, but the differences is a bit too small for my taste. There is also a thread here on head-fi somewhere where other people with an 12.9 iPad Pro also notices the same against the Mojo. However it seems that with the Poly the Mojo goes into a much higher level. Especially the soundstage all of a sudden opens up (the Mojo by itself really has a narrow soundstage to be honest). Disclaimer: I only use the Mojo and iPad Pro with my IEM’s (Campfire Andromeda with the upgraded Reference 8 cable). I never did a head to head test with full sized headphones.