I'd really like to know what airlines you are flying. The 12.9 iPad Pro is practically unusable on the flights that I've been on.
Here's a 13" Macbook Air on the tray table of a flight that I'm typically on. That is approximately the size of the 12.9 iPad Pro. With the person in front fully reclined (which is almost always the case) there is even less room.
Even when swapping out the ASK for the smart cover, the iPad Pro needs to be moved closer (due to the lack of clearance from the reclined seat in front)
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I ended up using a wire business card holder (bend slightly to adjust the angle) that fits in the tray table latch hook to watch videos from my iPhone or 7" tablet.
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