Apple iPhone 4 full review

The Apple iPhone 4 is the thinnest smartphone in the world with the highest resolution display ever built into a phone handset. Read our full Apple iPhone 4 review to find out if it should be your next mobile phone. Updated July 29 2010.

Also see iPhone 4S review

The Apple iPhone 4, as the name suggests, is the fourth generation of Apple’s game-changing smartphone. It’s already garnered far more publicity than the previous three models – if not entirely for the right reasons.

Few could have escaped mass-media news coverage of reception issues highlighted by Apple’s unusual choice of design, which sees the iPhone 4’s aerials fixed around the outside of the handset. But before we examine the minutiae of antennae, let’s look at the technology changes found in the iPhone 4, and how it compares to its own predecessors.

Apple makes a big play about the slimmed down casework. If you lay an iPhone 3G down next to the 4, you can plainly see the latter is thinner, matching the 25%-thinner boast. Yet in the hand, the iPhone 4 actually feels chunkier.

That’s entirely due to differences in the way the case is shaped between models – iPhone 3G and iPhone 3GS had a curvy form with rounded back and soft-radiused edges. But the iPhone 4 is a dense slab with square edges, seemingly heavier, although at 137g it’s only 4g more than an iPhone 3G, and 2g heavier than the iPhone 3GS.

Net result – it feels thicker in the hand. But it’s beautifully weighted and feels solid, against the 3G’s thinner-feeling form with its plastic back.

Front and back are now formed from toughened glass, and while we’ve not managed to scratch either side yet, we prefer to carry the 4 in a case that covers the back – the face that comes into most contact with the real world when lying down.


A simple comparison of screens between this phone and the 3G/3GS shows that there is in fact no comparison – the Apple iPhone 4’s display is richer, more colourful and much, much sharper. With four times the pixel resolution, that’s hardly surprising. You can now read – subject to eyestrain – every word on a webpage built for desktop PC dimensions, even fully zoomed out.

We noticed that small text on a webpage looked less bold, like a ‘light’ version of the font had been substituted. But compring back to an iPhone 3G screen showed that the older screens used plenty of anti-aliasing to reduce jagginess but make the type fuzzier. The iPhone 4’s typography is so clean, it looks almost lightweight.

All the extra graphics processing of four times the pixels has not slowed down the rendering of images one bit. In comparison to our 3G especially, the iPhone simply flies in its interface responsiveness. Pinch to zoom actions carry no lag, leaving pages and photos to scale up and down as quick as your fingers can dance over the silky screen.

Camera Time

Other headline features added to the iPhone 4 include two new cameras – facing fore and aft – which enable internet video calling and high-definition video shooting respectively. At present the only way we’ve found to use the video webchats is with Apple’s own implementation of video-over-IP, FaceTime. This works very well when it works – which is to say almost every time we tried.

With its vivid, sharp and essentially glitch-free video to enjoy, we can guess why Apple made the facility Wi-Fi-connections only. Even seven years after 3G-video calling was first promoted for mobile phones, the breadth of coverage and consistency of 3G connections is still too patchy to make reliable video chatting viable. Most phone networks’ strained infrastructure would probably fail further when hit by widespread videocalling.

Apple certainly didn’t invent phone video chatting, but it did turn it into something that’s a joy to use. Using Facetime really is a doddle. Make a regular voice call over GSM, and if both parties are on a WiFi connection you just press the FaceTime on-screen button.

Your voice call is terminated (so you don’t use paid-for talk-time) and you’re transferred to a purely data connection. You’ll see the image of your chatting partner onscreen, with your own face in a small, draggable thumbnail. Tip the phone sideways and images automatically adjust to fit landscape mode. And rather than keep the focus on yourself, you can tap an on-screen icon to switch to rear camera, showing your friend your point of view.

We found that rear-facing camera to give admirable results when used for snapping hi-res stills, or taking HD video. Still images are bright and finely detailed at their new-found 5Mp (2592 x 1936 pixel) resolution. Zoom in to actual size and you’ll see a little JPEG noise – but this kind of microscopic nit-picking is normally reserved for a review of a dedicated camera. A white LED flash helps indoor shots, with simple on/off/auto switching overlayed on the full-screen viewfinder. You can even switch to the video VGA camera here for easy group self-portraits.

But video recording is even better. We tried the video camera on the Thames boat-trip with some moving-water shoots, tortuous scenery to capture accurately, and the MPEG-4 compression engine took the challenge by recording sharp high-definition film with no motion artefacts whatsoever.


Multi-tasking was introduced with the iOS 4 update, and while we never missed its absence before, we now appreciate the real benefit of having apps running in the background.

More than just allowing social butterflies to have their Twitter app open all day, it means when you leave one app to start another, the switchover time is incredible quick, since the app is usually still loaded in the background, rather than having to be relauched.

This also means you’ll return to the last state that app was in – tapping Settings could take you to the menu a few pages down where you were last tweaking your keyboard layout, for instance.

The iPhone 4 has a large amount of memory by phone standards - 512MB of embedded RAM - which allows many apps to be all open at once. By double-tapping the Home button, you can see a Dock-like line of running apps, and force-quit them if desired.To do this, just press and hold an icon until a No Entry flag appears in its corner, then tap it again.

We found that in daily use, dozens of applications would still be loaded into memory - more than 40 is not unusual. The iOS 4 memory management allows unused apps to gracefully quit when the phone does need more physical RAM.


In contrast to hiding a radio aerial inside the case of a mobile phone, keeping it outside should be a Good Idea.

But an uninsulated aerial that’s in inconsistent electrical contact with a large semi-conductive object – the human body – may be less reliable. There's been plenty of talk already of the consequences of detuning aerials, especially when fingers bridge the gap between the Wi-Fi/Bluetooth/GPS antenna (left side) and the GSM/3G antenna (right and bottom edges).

It must be said that despite using it without a case for a week, we experienced few dropped calls or problems with reception on the iPhone 4, using it on the O2 network. And subsequently, no issues at all once we’d swapped out that SIM for a Vodafone card.

What we did notice was that compared to iPhone 3G and other recent phones, the iPhone 4 had the best mobile reception we’ve experienced. It could really hang on to a data connection, for instance, deep into a train tunnel where other phones would be announcing No Signal.

On top of new functions and slick running of existing capabilities, probably the single biggest benefit has received less attention – battery life.

Many smartphones struggle to get through one day when used actively, yet our sample was still running into its third day of use. That's with 3G and Wi-Fi switched on, and taking photos and intermittent internet surfing.

Battery capacity has increased, but only by around a third. Yet somehow, despite a more powerful processor, plus a multi-tasking OS, more powerful cameras and extra sensors, the new handset’s features have been truly tempered by longer battery life.

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