The first thing you notice about the iPhone 3GS is its speed. Thanks to a faster processor it feels much snappier than the 3G.
You'll notice apps opening very quickly and in a side-by-side test over WiFi, the BBC news site loaded in seven seconds, compared to 12.5 seconds on the iPhone 3G and more than 14 seconds on the original iPhone.
The battery life is much improved too, meaning we could last a whole day without going low on battery. Interestingly, Apple isn't claiming any increase in talk time over the previous model, but video, music playback and web browsing all show improvements.
The iPhone 3G was rightly criticised for its poor 2.0 megapixel fixed-focus camera without a flash. The new iPhone 3GS still lacks a flash, but brings a 3MP-resolution camera with a macro lens to the party.
Focussing is automatic, but you can tap on the area of the screen and it focuses also. The white balance and exposure are automatically adjusted too, which is pretty clever. The extra megapixels help enormously in picture quality, but taking pictures in low light levels remain a problem.
The macro lens takes good close-up shots too, without the blurring that afflicted previous generations, but it's still only comparable to a camera that some three-year-old mobile phones have.
More importantly, the iPhone 3GS is now video capable. And the really clever thing is that it has capabilities for editing video on the phone as well – just drag the start and end points of your clip and tap the trim button and you're done. It all works surprisingly well.
Once you've shot your video you can upload it straight to your MobileMe gallery, YouTube, or email or MMS it. Bear in mind that it takes a long time to send video, even on a WiFi connection, so you're only going to want to send very short clips. Uploading to YouTube was flawless, MobileMe (perhaps slightly predictably) proved less so.
The new Compass app is, as you'd expect from Apple, gorgeous to look at, but probably not worth getting all that excited about.
In contrast, the new oil-resistant screen is fantastic – it genuinely works – just wipe the screen on a piece of clothing and all the smudgy fingerprints are gone.
Also new to the 3GS is Voice Control. Press and hold the Home button until you hear a beep then call a contact from your address book by saying "Call Graham", for example. Voice Control also works in the iPod app, where you can request music by voice command, however, this can be a bit hit and miss with exotic band names.
For first-timers If you're a potential first-time iPhone owner who hasn't made the jump yet, then the time is now – the iPhone 3GS has finally got everything you'll need – but the real question is, is it worth paying to get out of an existing iPhone 3G contract to get better camera and video recording?
On balance, probably not – you get almost all the new features by upgrading to the 3.0 software for free. 3G owners would be better off waiting until your contact expires and then upgrading, unless of course, you really want to shoot video on your iPhone, because it does it really well.
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