I really think that the mini is too small, on the other hand I find the standard iPad too large to conveniently fit on the yoke. So the mini it is for me…
Left knee iPad mini, right knee pen+paper. I looked at PROs, but seemed too thick and heavy. I also thought an iPad might not always be ready to accept handwriting.
I don’t think one size fits all, and the “best” size is the one for the intended application (and not meaning software) and available cockpit space. A Mooney is an entirely different story than a CJ3.
The best size for a side window (e.g. Cessna 172) is likely the mini. Perhaps a medium size would work ok in a large twin or jet with more side window space and general elbow-room.
For a kneepad or general lap use, the 9.7-10.5 is likely best although I know an instructor (always sitting in the right and not normally pilot flying) who has the big Pro model…. but that’s slightly different than PIC knee usage.
For a yoke mount, medium or smaller is probably ok… and a matter of preference.
For panel mounting is a “poor man’s PFD”, probably the largest available is the most desirable, panel space permitting.
Here are a couple articles with some comments:
Best iPad for pilots
Different iPad sizes in an airplane
The iPad pro 11" looks like a decent size iPad. I am thinking of upgrading to this as it’s not much heavier than the iPad mini, but much lighter than my iPad
But it’s holder is humongous and very heavy. I am thinking of buying a silicon case and using cable ties to mount to the arm from the suction cups. (Currently it has two screws that keep the holder onto the mount). The mount when properly installed is going nowhere, but I think it would be beneficial if I removed that weight and modified it so that I could have the iPad on the Pilot side and see my charts/Sky Demon at eye level for when I start the instrument rating.
See iPad Pro 11. https://ipadpilotnews.com/2019/02/how-do-different-sizes-of-ipad-fit-in-an-airplane/
Before Peter mentions it… 
If you’re worried about over-heating, an iPad mini with one of these is a great solution. I used this all summer flying down to the Med and back in sweltering temps and it did a great job. Not cheap but money well spent for peace of mind.
jgmusic wrote:
If you’re worried about over-heating, an iPad mini with one of these is a great solution.
The only time my pro overheated was when spending too much time on my kindle by the pool (+ no wind) in the summer in Okinawa.
I haven’t had any issues during the summer flying DA40s (large bubble canopy) to Portugal, in sunny skies. (and yes, I was charging it, although not with a 12v (inop) but with my spare battery, since I was doing ~7h actual flying per day).
That’s very impressive, Noe, but you do hear stories of iPads overheating… It’s not something I’d like to take a chance on in the air
I think it is fair to say that as tablets, particularly Apple ones, are updated with faster processors, they dissipate more and more heat. Hence the ever higher charging currents, for example.
Android ones seem to have got left behind in comparison…
Funnily enough, desktop PCs and laptops have gone the other way. Once they reached about 3 to 3.5GHz, they went to lower power, and the latest CPUs dissipate much less heat than the old ones. So the market for the huge coolers like this has dropped considerably.
Anecdotally also it appears that Foreflight draws more power than other satnav tablet apps. The Golze ADL app also draws a lot of power (on android at least; not tested it on IOS).
On hardware heating: it depends if you are happy to limit processor speed, kill background apps and online data…
Personally, I prefer android stuff for this, I may get a slow SD run after but I think this should be ok on most new devices
My Galaxy tablets are from 2013 and run only SD+PDF while in-flight, I never had an issue with heating but my phone always gets crazy
I use an 11" iPad Pro in an Otterbox case running ForeFlight/Jepp etc. The size is just fine in a DA62. Hopefully you will get an idea of size if you can see my left hand holding the tablet!
