The new letter in Apple's iPhone range stands for 'Speed'. It lives up to the promise.

Rather than bringing out an entirely new model, Apple have chosen to improve on their celebrated iPhone 3G. The 3GS comes with a faster processor, more memory, and better general performance than the 3G, all leading up to a smooth, fast experience that will feel instinctive.

The "speed" that Apple are aiming for is reflected in all of the upgrades they've made to the iPhone. The design may have stayed mostly the same, but the new coating has been changed to an oleophobic, fingerprint-resistant surface which reduces potential smudges and makes the screen easier – and faster! – to clean.

The expanded processer means that the new iPhone is more responsive than its predecessor, with applications that open and close at the mere touch of a finger, with very little keystroke lag. Mail, Safari, Maps, and Notes applications are exceptionally fast, and nearly all third-party applications from the impressive Apple App Store have improved in their speed, too.

The level of memory is up, too, from the iPhone 3G's maximum of 16GB to an impressive 32GB.

To upgrade or not?

A new software update may equip your iPhone 3G with all the new features that you'd want. It includes MMS, a landscape keyboard, Internet tethering, and Voice Memos. Additionally, there have been complaints about the iPhone 3GS's screen as compared to the iPhone 3G, with some customers unhappy with the new dimmer, warmer screen as compared to the iPhone 3G. Colours look slightly weaker in a side-by-side comparison; you may decide that you prefer the clarity of the iPhone 3G.

However, upgrading to a new phone comes with a host of new hardware features including Voice Control, a built in compass, and a much better camera.

The iPhone 3GS's camera has 3 megapixels as opposed to the 3G's 2, and allows you to find a focus point by tapping on the display screen, despite still lacking a flash feature. Additionally, the iPhone 3GS now allows video recording in VGA quality at 30 frames per second, with quality results. It includes a clever focusing control by not using autofocus, with the result that your finished film will have a steady focus that remains still even whilst experiencing sudden movements.

The iPhone 3GS also allows you to edit video clips on the phone, with a frame-by-frame editing bar that allows you to trim and review your video, though new users should be warned that the iPhone does not save an edited video as a new file, but replaces the original version. From there, the iPhone 3GS allows you the options of emailing the video, sending it via MMS, sending it to a MobileMe account, or putting it straight onto YouTube.

Additionally, the battery life of the iPhone 3GS is much improved upon the iPhone 3G – though still a little less than would be totally desirable! – and of course the faster processor and greater memory capacity cannot be installed in a software update.

If you're nearing the end of your contract, you might decide to upgrade. Check out some of Optus's (1300 137 897) great cap plans, or Vodafone's (1300 106 571) low cost cap plans.