With the iPhone 5, reviewed, Apple had to strike a balance between making changes and keeping things the same so existing iPhone owners would feel at home. Here's a rundown of what the new iPhone 5 features are.
1. Bigger 4in screen
The first thing you notice about the iPhone 5 when an iPhone 4 or 4S is put next to it is the dimensions. It's taller and thinner and, if you're comparing the white versions, the bigger screen is obvious. On the black versions, when the screens are off, it's harder to see the difference.
Until the iPhone 5, every iPhone shared the same 3.5in display, but the extra half-inch means Apple has been able to cram in 1136x640 pixels, and an extra row of Home screen icons.
Importantly, though, it's now a 16:9 screen rather than 3:2, so it's better suited to watching TV shows. You'll still see black bars when watching movies, of course.
A subtler change is that the display has a built-in digitiser, removing a layer compared to the older iPhones, and enabling Apple to make the iPhone 5 that much thinner.
The new screen has more saturated colours than the 4S's, but has the same brightness and contrast.
The new A6 processor may not be the quad-core chip some people expected, but it's not short of speed. The iPhone 5 feels amazingly quick, loading apps almost instantly, being extremely zippy in general.
If you're planning to upgrade from an iPhone 3GS or 4, you'll be staggered at just how fast the iPhone 5 is. Everything is faster from web page loading times to firing up the camera and taking a photo or video.
Graphics performance has doubled from the iPhone 4S, so games run better than ever.
In terms of megapixels, nothing has changed with iPhone 5's rear camera. However, it's a new 8Mp sensor and lens - plus the much-vaunted sapphire crystal cover. The latter is extremely scratch resistant, so even if the rest of your iPhone looks rather battered in a year's time, photos should still look as sharp and blemish-free as the day you got it.
The rear camera has come under fire for purple flare, where some images have a mauve haze over parts of the photo, but we've yet to see the phenomenon ourselves, and we've got half a dozen iPhone 5s in the office.
The fact is, although it still has a tiny lens and no optical zoom, the iPhone 5 is capable of capturing stunning quality. It won't match up to your DSLR, but it will already be in your pocket ready to shoot when the moment arises.
Video, too, is excellent. Like the photos, video is marginally better than footage from the iPhone 4S. Stabilisation also seems improved.
Again, if you're upgrading from an iPhone 4, the difference is much more noticeable. The extra detail is obvious, but better performance in low light, and the ability to keep tapping and capturing photos is almost magical.
Plus, you get the new iOS 6 panorama mode, and the ability to capture still images while shooting video. The iPhone 4 has to make do without these useful features. See example panoramas shot on the iPhone 5
The iPhone 5's front camera has seen the biggest upgrade, moving from a frankly rubbish VGA version on the iPhone 4 and 4S to one that can capture 720p video and garners Apple's iSight moniker.
Audio is also improved thanks to three microphones: one at the bottom as before, plus new front and rear mics to improve sound in both videos and also FaceTime calls.
4. iOS 6
We've already mentioned it, but the iPhone 5 comes with iOS 6. As you're no doubt already aware, this has plenty of new features including Apple Maps rather than Google Maps.
The show-off-to-your-mates Flyover feature is highly impressive, with scores of cities modelled in 3D. However, the loss of Street View in Apple's maps is a shame. You can still access Street View from Google Maps in the Safari web browser, though.
The real issue is that Apple's maps aren't finished. The app has been widely panned for lacking points of interest, even major railway and tube stations, and reviving long-defunct shops including Woolworths in the UK.
However, apart from this admittedly bad showing, there's a lot to like about iOS 6. Siri is now more capable. The virtual assistant can tell you where you are, give you directions, book a table at a restaurant, look up film listings and local businesses.
There's integration with Facebook, shared Photo Streams, improved email (including a VIP inbox for your close friends, family or colleagues), new phone and internet browsing features plus a new Passbook app for tickets and coupons.
For more, see our iOS 6 review.
The iPhone 5 is the first Apple device to drop the old 30-pin connector and replace it with a new, smaller all-digital port: Lightning. This has a reversible design so you don't have to worry about which way you plug in the USB cable: it works both ways. It supports USB 2.0, but not the faster 3.0 standard.
The headphone jack has been moved to the bottom of the phone and the iPhone 5 comes with Apple's new EarPods, which also act as a headset for calls.
If you've spent a lot of money on accessories and docks for older iPhones, Apple offers several adaptors so you can still use older 30-pin accessories. The basic adaptor costs £25 and a short Lightning-to-30-pin cable is pricier still at £30.
The Lightning port has eight pins and can dynamically reassign their functions. What this means is that Lightning cables and adaptors include processors, so it's unwise to buy unbranded cheaper versions as there's a chance they won't work.
However, things aren't necessarily that simple. We've tested out the adaptor and although it seems to hold the iPhone 5 steadily in place on a speaker dock, there's no support for video output, so your existing 30-pin to HDMI adaptor won't work. Apple says adaptors with video capabilities will be available later.
6. Wi-Fi and 4G
One of the other big updates is that the iPhone 5 has an LTE modem. This means it supports 4G in the UK - currently on EE. For more, see: our complete guide to 4G.
Yet another update for the iPhone 5 is a nano SIM, which is smaller than the micro SIM used by the iPhone 4 and 4S.
Wi-Fi has also been improved in the iPhone 5, with a dual-band 802.11n radio. This means it can connect on either 2.4GHz or 5GHz with compatible hotspots and wireless routers.
7. Dimensions and construction
The iPhone 5 measures 124 x 59 x 7.6mm, and weighs 112g. It feels incredibly thin and light to hold, and is stunningly attractive.
Build quality is first-class, but because of the continued use of glass and - now - anodised aluminium, is more susceptible than ever to cracking and scratching.
It's almost a crime to put the iPhone 5 in a case, but if you want to ensure it stays in pristine condition, you won't want to keep it in your pocket along with a bunch of keys.
Instead of a central metal band with front and rear glass covers (the design of the iPhone 4 and 4S), the iPhone 5 has an aluminium 'unibody' with glass inserts at the top and bottom of the rear panel. This is one reason it's so thin, and it also means the display is much easier to replace than before, as it's the last component to be fitted, rather than the first.