My 3GS was truly on its last legs, so needed to upgrade, but admittedly, it's no different really. Plus I've turned off most of the new features.
iMessage - usually sent as a text message after a 10min delay anyway and uses-up data allowance, so turned it off and stuck to my 600 free text messages per month
Siri - rarely works properly so turned it off after a few weeks
Reminders - never used it.
Location-based reminders - very specific locations and uses A LOT of battery, so never use it.
Only good thing is the battery. I can go well over 48hrs between charges now.
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Other than first time new users, there's no _need_ for the 4S.
However the brilliance behind it is the huge profit it brings Apple in re-using the same design two years in a row. The cost savings to Apple is far beyond what many would believe.
Furthermore it's the incredible brilliance of the late Steve Jobs ability to convince the public that in order to "be cool" you must be seen with the latest Apple gadget. Proof of which is seen daily here in the forum. The man was the worlds best salesman. Customers clamoring for anything Apple.
All one has to do is read the responses to rumors with the slightest bit of "information" the eager followers say things like "take my money please".
Now in lieu of the master spin man, Apple will surely have to scramble to keep up that momentum & insatiable demand. Mark my word, many will go deep into denial about this statement but there's no denying it if one is honest and aware.
I agree completely. I hated the design of the iPhone 4 and when the 4S came out, hated that too.
But is amazes me that no other phone really comes close. Everytime I see a friend with a Galaxy S2 I ask to have a play as I really want one, but in that short time find several flaws that persuades me to follow along like every other Apple sheep.
The moment a truly Apple-beating phone (and 'eco-system') comes out, I'll jump. But until then, I'll blindly buy each iPhone with quiet resignation.