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When I was an Android user I was on one extreme where I would upgrade every 3-4 months via Craigslist.

The 4S has brought me back to the other side of things. It's the first handset I could see myself with for even longer than my two year contract.
 
Only if I'm impressed by the keynote and the iPhone. Then I buy a new one. A performance upgrade just doesn't cut it.
 
The good thing about iPhones and other Apple products is the resale value. I break even every year reselling my old phone.
 
Tend to upgrade when there is a redesign. I still have the 4 as the jump to the 4S wasn't big enough to justify it. Hopefully my provider will give me a good deal when I jump to the 5.
 
I started at the first generation then 3GS, I broke my 3GS and I was able to get the iPhone 4 .. I'm sticking to the trend of skipping over the "S" versions. If that will continue to still exist of course.
 
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