I generally update every year.
I was going to hold out till the air 3 but the lcd being laminated to the glass made the upgrade worth it alone. The upgraded ram is wonderful as well.
Typos bear no resemblance to the overuse of slang. Typos happen because people can't type(o) or their spull chucker doesn't pick it up or maybe they can't spull.
Gotta go rock dinner. But those damned rocks break my (or is it "mines"?) teeth every time.
Does anyone else find that the pre-Air iPads are easier to rock because of the slightly curved back?
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Use an Air 2 at home for browsing, media consumption, blogging (I can type pretty fast!) and basic photo editing and spreadsheet tasks (Excel is pretty good).
I use a Mini at work as a 'side kick' device, for taking notes in meetings, listening to music while concentrating, reading long documents and responding to email away from my desk.
I love my iPad mini retina... But I'm hoping the mini 4 brings some good upgrades because I want touchid. Mini 3 was a hideous upgrade so I skipped it.