Two points:
1. The iPhone 4S is very powerful. In terms of raw performance, it was a huge leap for Apple, and the phone industry in general.
2. For those people that insist the iPhone 4 and iPhone 4S are the same...please stop with that...
I still believe that the iPhone 4S is a really small upgrade. The upgrade from the iPhone 3G to the iPhone 3GS was (felt) much bigger. The iPhone 4S' big thing is Siri - but it's really limited (in terms of language support).
I do believe that we'll see the benefits from the iPhone 4S later this year and next year but right now, graphically intense games do just fine on the iPhone 4 as well.
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Let me put it differently why I believe the iPhone 4S is a much smaller upgrade. In a nutshell, this were the 'big things':
- Full HD 1080p video recording with stabilisation
- 8 megapixel camera
- Dual-core A5 chip with better GPU
- Siri
When the iPhone 3GS was announced, these were the 'big things':
- 3.2 megapixel camera
- Video recording
- Better CPU and GPU
- Coating against fingerprints
- Compass
- Better battery life
- Voice Control
I'm willing to give up "Compass" and "Coating against fingerprints" as 'big changes', but that leaves us with plenty of new features.
So, now why is the iPhone 3GS a big upgrade, and why is the iPhone 4S NOT a big upgrade?
Camera
First up is the camera. The first two iPhones had a 2 megapixel camera while the iPhone 3GS had a 3.2 megapixel camera. It was a necessary improvement because this 3.2 megapixel camera might seem crappy now, but back than it was a
huge improvement over the iPhone 3G.
However, the iPhone 4S has an 8 megapixel camera compared to the iPhone 4's 5 megapixel camera. While I'm not against improvement, the five megapixel camera from the iPhone 4 is already quite good. And thus, on the camera side it feels like a much smaller improvement.
Video recording
The iPhone 3G does not record video. The iPhone 3GS was the first iPhone to ever record video. The video quality wasn't great when viewed on a large screen, but it finally was there. It's
big to go from no video recording at all, to - well - video recording.
The iPhone 4 already did 720p HD video recording - video quality is good. I must agree that it's a good advantage that there is now 1080p video recording
with video stabilisation - it is, however, not big enough for most people (
not for everybody) to upgrade.
Dual-core A5 chip with better GPU
The iPhone 3G had a bad CPU and a bad GPU. The iPhone 3GS really improved on this and it delivered a
much better experience. The App Store was becoming bigger and bigger, so the better graphical capabilities were a + as well.
The iPhone 4S also got a much better CPU and GPU. This time, however, it wasn't really necessary. There's a much smaller difference in performance between the iPhone 4 and iPhone 4S, than there was between the iPhone 3G and iPhone 3GS.
To give you an idea of what I mean: the iPhone 3G was driving 50 km/hour, while the iPhone 3GS was able to drive 100 km/hour. The iPhone 4 was driving 120 km/h while the iPhone 4S 'only' drives 130 km/u.
Voice Control (Siri)
I like the idea of Siri: one day being able to truly talking to your phone as if it were your assistant. In fact, it's great they are working on this but let's face it: it's still not good enough, it's not available in enough languages and some features don't even work abroad (like looking up restaurants via Siri).
And we've already had Voice Control since the iPhone 3GS.
It's improved, but it is definitely not mature enough. Not yet. Apple even advertises it as a beta product - that says enough.
Other
And that's really it for the iPhone 4S. Some other
new features the iPhone 3GS got was a coating against fingerprints, a compass (which was really nice to use in the Maps application) and better battery life. Some people even report worse battery life on the iPhone 4S.
Conclusion
And that's why I find the iPhone 4 to iPhone 4S upgrade smaller than the iPhone 3G to iPhone 3GS upgrade. At
this point, it just isn't big enough.
But Apple is changing that...
The iPhone 4S will be much more important as soon as iOS 6 launches though - because only than, the big differences will appear. Such as turn-by-turn navigation. FaceTime over 3G.
Indeed, that's right: a full year after the iPhone 4S launched, we will see the first big benefits of owning an iPhone 4S over an iPhone 4.
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So, uhm, this was what I wanted to say. I'm sure the iPhone 4S will become more and more awesome (compared to the iPhone 4 and iPhone 3GS) as soon as more firmware updates roll out - but right now, there isn't really a big difference.
So I would advice anyone that's buying a new iPhone, to get an iPhone 4S - but until iOS 6 launched there's practically nothing for iPhone 4 users to be jealous about.