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Having been going through these very decisions, we have a couple of observations that maybe will help some others.
1. Some suggested the Air instead of the Mini if one already has an iPhone 6+. OTOH, keep in mind that the
Mini's screen is more than double the size of that of the iPhone 6+! Roughly 30 sq. in. vs. about 13. That's 2.3x as big!
2. The Air 2 vibration is a minor issue to us (YMMV).
Key is that the Air 2's sound is clear and loud. (We found it impressively loud and clear even over the usual din at a Best Buy store!)
3.
We skipped the Air 2 last year; too high a cost for too little gain!
a. Yes, better camera in the Air 2, but we don't use the iPad Air for photography.
b. Yes, fingerprint scanner, but the Air stays at home and the instant on/off of a Smart Cover type case is even faster than Touch ID.
c. Yes, faster CPU, but the Air is plenty fast. Even our original iPad is going strong and handles streaming and most apps fine, with one exception.
d. One big negative to the Air 2-- no screen rotation side switch on its side.
4. This year, though, the upgrade decision became a no-brainer when Staples offered the Air 2 with 64gb for only $449!
The key, performance-wise, is that Safari reportedly doesn't keep reloading tabs all the time. [
Confirmed in use-- it's incredible to see and experience. Return to Safari and there could be a momentary delay on the first tab, but every other tab displays instantly!] (OTOH, for users who view only 1 web page at a time, that's not a big deal!). Plus, we figure it will handle iOS 9 and 10 better.
5. Not sure we understand the one-handed use thing being a factor at all! Ours (whether Minis or Airs) are either in stands, or resting in our laps or on our chests. Typically, when free-holding, we still use two hands--more secure grip and easier to use (type, tap, etc.)
6.
The Mini color gamut thing matters to many; but was inconsequential to us. We have no problem with the screen on the 2-- in fact, it shows the colors of Google links as blue not purple as the Air does! A couple of other apps also show blues *better* on the Mini.
7. Now, for us, whether to upgrade a Mini 2 to a 4 rests with the camera upgrade (purportedly substantial improvement) vs. the cost. (Otherwise, the other upgrades and decisions are similar as to going from Air 1 to 2). [
Update: we found that the Mini 2 camera and that of the Air 2 showed marginal differences; expect the same to be true of Mini 2 and 4 camera. Here's a great comparison of Air 1 and 2--they tout differences, but most are only apparent on blowing up the photos greatly--and, in several cases, Air 1 looks better!
http://www.imore.com/ipad-air-2-vs-ipad-air-camera-comparison
S
imilarly, little apparent difference between iPad Air 2 and the iPhone 6! http://www.imore.com/ipad-air-2-vs-iphone-6-camera-comparison ]
We find 16gb getting a big cramped... But if we had no Mini, the new price of $320 for a 32gb would be appealing!
8.
In general, forget the specs; the key between the Mini and the Air is which size iPad you want!
If you have the $, get both the Mini and the Air! We have both and find them useful for different things-- and, it's nice to have another iPad in the house for other family members to use.
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