One of the best things about the iPhone 4 was its incredibly long battery life which helped made it the smartphone to beat. The iPhone 4S matches the battery life of its predecessor in our informal tests, which is no mean feat given that it has a more powerful dual core A5 processor instead of a single core A4 chip.
The iPhone 4S matches the battery life of its predecessor in our informal tests, which is no mean feat given that it has a more powerful dual core A5 processor.
The 4S lasted just over two days in light-to-moderate use, such as web browsing over WiFi and making a few texts and calls. More heavy use, such as web browsing over 3G, making lots of calls, using Siri extensively and using GPS reduced battery life to just under 24 hours. With all wireless connections disabled, the battery lasted just under nine hours when playing H264 video on a loop and it lasted just under 57 hours when playing an MP3 playlist on a loop - both impressive times.
Visual arts
Another feature we loved in the iPhone 4 was its Retina Display. The 960x640 pixel resolution wasn't used to simply display more information, but was instead used to create a high pixel density of 326 pixels per inch. This led to incredibly smooth, crisp text and images that is very easy on the eyes.
None of this has changed with the iPhone 4S which has an almost identical screen. One noticeable difference however is the warmer, yellowish tinge to the screen which makes the screens of other phones seem cold and blue in comparison. The IT Pro office was firmly divided between those who liked the warmer tinge and those who didn't.
Some may be disappointed that Apple didn't follow the lead of Android and Windows Phone manufacturers by increasing the size of the screen, but we find larger screens less comfortable to use single handed and for those with small hands.
Verdict
Although it's not perfect, the iPhone 4S is the best smartphone we've seen yet with a great screen, high-quality camera and a slick user experience thanks to iOS 5 and a broad selection of apps from the App Store.
Most owners of the iPhone 4 will still be tied to contracts preventing them from upgrading, so the iPhone 4S is really aimed at owners of the older iPhone 3GS and smartphones running competing operating systems. Those users, as long as they can live with Apple's odder design decisions such as the lack of memory card slots, should seriously consider upgrading.
For iPhone 4 that can upgrade, the free iOS 5 upgrades means the iPhone 4S isn't as compelling so they should hold off for now unless they're frequent camera users or drive often enough to make use of Siri.
Connectivity: GSM 850/900/1800/1900, 3G HSDPA/HSUPA 850/900/1900/2100
Display: 960 x 640 pixels, 3.5in
OS: iOS 5
Camera: eight megapixels with flash rear-facing, 0.3 megapixels forward-facing
GPS: A-GPS
Processor: Apple A5 dual-core, clock speed undisclosed
Bluetooth: v4.0
Wi-Fi: 802.11 b/g/n
Memory: 32GB internal (16 and 64GB models available)
Dimensions: 115 x 59 x 9 mm
Weight: 140g
Battery: Lithium-Ion undisclosed capacity
