Apple iPhone 4 32GB review

While previous revisions of the iPhone have essentially been small updates to the existing design, the iPhone 4 feels like a new phone. It's the thinnest iPhone yet at just over 9mm, being a little narrower than the old models, too.

The front and rear are made of aluminosilicate glass, which is said to be 30 times stronger than plastic as well as highly scratch resistant. It's the same stuff that helicopter windscreens are made of, and it also has an oleophobic coating which is incredibly easy to clean.

The stainless steel strip around the edge has several functions. First, it provides structural rigidity and second, it acts as the antennae for the phone, WiFi and Bluetooth. Build quality really is first class, and the iPhone 4 feels better built than any other current smartphone.

One of the main new features is a front-facing camera which enables you to make video calls. Apple calls this FaceTime, and it's currently only available via WiFi. To use it, you call another iPhone 4 owner and then invite them to establish a video call. Once this is running, the voice call is ended. We were surprised about the decent quality and frame rate, as well as how quickly you can switch between the front and rear cameras - useful for showing your surroundings as well as yourself. We found that FaceTime sometimes didn't work at all, and it also needed a strong WiFi signal.

Apple says that, in future, developers will be able to make applications that work with FaceTime and should allow you to make video calls with devices other than iPhone 4s. However, we'd also like to see the ability to use FaceTime over 3G, but that's an issue for mobile operators to sort out.

The rear camera has been upgraded to a five-megapixel, back-illuminated sensor, and can now shoot 720p HD video. Rather than keep the same sensor dimensions as the 3GS's camera, the new camera has the same size pixels and a larger sensor. This leads to far better quality images and video in dim conditions. Although our test photos were a little noisy, it was luminance noise rather than chroma (colour), so it wasn't too distracting. The only real issue was poor white balance when using the built-in LED flash. However, in good light, the camera was quick to focus and there was very little shutter lag.

When taking video, there's no warning if you shoot in portrait mode, but the quality of the footage was again very good in bright light. Our test clips rivalled the Flip Ultra HD, as long as you keep the phone still, and audio wasn't bad either. The LED can be used to illuminate your subject at night, but it's only good for very close objects. Essentially, video and still photo quality is a major leap from the 3GS.

It's a little tight of Apple to charge £2.99 for iMovie, but it's money well spent. With it, you can quickly cut together clips you've taken, add a theme and music, then upload your creation to YouTube. The iPhone 4's built-in GPS receiver means that all videos are geotagged (as are photos), and the Travel theme uses information this to automatically create a map with a dot showing the location and a thumbnail of the video. You can easily change the default dissolve transition between clips, as well as trimming clips to use only the portions you want. To achieve all this on a 3.5in screen is little short of a miracle.