I can understand why Apple have stuck with the external antenna and glass design, the form factor is great, it is light and comfortable to hold and lets face it, Jonathan Ive and the rest of the designers at Apple have spent too much time, money and effort to drop this design after one iteration of the iPhone. The only difference in the external design of the 4S from the iPhone 4 is that the antenna is the same one used in the Verizon iPhone 4 which had been modified slightly to attempt to fix the signal issue that the iPhone 4 was infamous for. Incase you haven't noticed the difference, the GSM iPhone 4 had 2 black notches on the bottom left and bottom right of the antenna and one just to the right of the headphone jack whereas the Verizon iPhone 4 and the iPhone 4S have 4 black notches on the bottom and top of the device on the left and right sides.
Now here is where the iPhone 4S really sets it self apart from it's baby brother, the iPhone 4.
It features the dual core, 1GHz A5 chip that first debuted in the iPad 2 which makes for greatly improved performance. Apps load quicker, web pages render faster and there seems to be almost no lag or slowdown when trying to perform processor intensive tasks. The processor is also more energy efficient than the A4 chip found in the iPad and iPhone 4, with slightly improved battery life when making calls, using apps or web browsing over 3G. Although inexplicably, the iPhone 4S loses an hour of battery when browsing the web over wifi.
Apple have also greatly improved the antenna this time around. The 4S intelligently switches between the two antennas meaning the signal is greatly improved and coupled with the new processor, the download speed on 3G is massive! On my previous phone, the iPhone 3GS I would average out at .9Mb per second, with the iPhone 4S however, I now get 2.9Mb per second. In addition to this, I get 3G coverage in more places than I ever could with the 3GS.
The place where the upgrades to the 4S really shine through is the camera.
It now sports an 8 megapixel sensor and will shoot video in 1080P full HD. Below are some test shots I took with the camera.
Colours really stand out and up close shots look more detailed than ever. I am however a little disappointed that the front facing camera has had no upgrade at all since the iPhone 4 and it is a little alarming that there is no way to choose which resolution you would like to shoot video in, it just shoots in 1080P whether you want it to or not meaning if you film a lot of video you may find the storage on your phone running out quickly.
I am not going to go through the finer points of how awesome or not iOS 5 is(I'm looking at you, Reminders), that's for another review. I am however going to talk about one software feature that is(for now) exclusive to the iPhone 4S and that is the personal voice assistant, SIRI.
It is only available in US, UK and Australian English, French and German and it can only search for places and businesses in the US for now. Maybe integrating yell.com for UK users will solve this but who knows? Its in beta at the moment and there are still many many bugs that need ironing out.
Summary and Should you Buy?
In short, there are some great features on this phone for new and old iPhone customers alike but if you've already got an iPhone 4 there aren't too many major differences to make this an essential purchase, you could consider it if you were at the end of your iPhone 4 contract but if you're not, just wait for the iPhone 5. It is however a huge step up from the 3GS making this an essential upgrade if you were looking at a new smartphone after your iPhone 3GS.
This phone is by no means perfect but it is phenomenal at what it does; it creates an wonderful and engaging iOS experience.