iPhone 6S vs iPhone 6: What's new?

iPhone 6S vs iPhone 6: See how Apple's new smartphone compares to last year's iPhone

After months of leaks, the iPhone 6S is now available to play with. Like most "S" upgrades, it tweaks the formula Apple introduced with last year's iPhone 6.

There's an updated camera, clever 3D Touch tech employed in the display, and new build materials used in the construction.

But should you be thinking about upgrading your iPhone 6? Let's take a closer look at everything Apple is introd

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iPhone 6S vs iPhone 6: Design

iPhone 6S: 7.1mm thick, 143g, series 7000 anodised aluminium back, Space Grey/Silver/Gold/Rose Gold

iPhone 6: 6.9mm thick, 129g, series 6300 anodised aluminium back, Space Grey/Silver/Gold

While it's still a great-looking phone, the iPhone 6 was probably the least visually appealing iOS device to date. A combination of plastic antenna bands, overly curved sides and a protruding camera lens combined to create something that lacked that typical Apple sheen.

Unfortunately, there hasn't been a dramatic change for the iPhone 6S. In fact, if anything the iPhone 6S design is marginally worse, thanks to its being 2mm thicker and 14g heavier. There's a worthwhile reason for that, though.

Related: iPhone 6S vs Galaxy S6 and iPhone 6S Plus vs 6S

One improvement is the upgraded build material – series 7000 aluminium as opposed to the 6300 series used in the iPhone 6.

This gives the phone a bit more rigidity and should ensure there's no repeat of the "bend-gate" scandal that took the gloss off the iPhone 6 Plus launch.

Compared to the iPhone 6S Plus, it's significantly easier to manage in one hand and remains one of the most durable, well built phones available.

iPhone 6S vs iPhone 6: Screen

iPhone 6S: 4.7-inch, 1334 x 750 IPS LCD, 326 ppi, 504 nits brightness, 3D Touch

iPhone 6: 4.7-inch, 1334 x 750 IPS LCD, 326 ppi, 504 nits brightness

The iPhone 6S screen is identical to that of the iPhone 6 before it, which means it's a decent 4.7-inch 750p IPS LCD display. It's not the best screen on the market - that honour belongs to the Samsung Galaxy S6 - but it's generally a bright, vibrant, and crisp effort.

While the iPhone 6S's screen is nothing new, the biggest addition to the phone relates to the way you use it.

Similar to the Force Touch feature found on on the Apple Watch and latest MacBook, the newly named 3D Touch has found its most sophisticated application yet on the iPhone 6S.

3D Touch detects how hard you press on the screen, and Apple has used that to promising effect. Pressing hard on an Apple app icon will bring up short cut options, rather like right-clicking on a desktop.

You can also use it to preview links, emails, and photos. It'll take third party developers to really make 3D Touch part of the furniture, but even at this early stage it's easy to see what a transformational technology this will prove to be.

3D Touch is the reason why the iPhone 6S is a little thicker, while its new Taptic Engine (a sophisticated vibration motor) is the main culprit for it being heavier. It's well worth the weight.

iPhone 6S vs iPhone 6: Performance

iPhone 6S: Apple A9 64-bit dual-core 1.84GHz, PowerVR GT7600 GPU, 2GB RAM

iPhone 6: Apple A8 64-bit dual-core 1.4GHz, PowerVR GX6450 GPU, 1GB RAM

No iPhone yet has shipped with more than 1GB of RAM - until the arrival of the iPhone 6S. The benefits are obvious to anyone who has used iPhones in the past.

Jump back to a web page or app through the new-look multitasking menu - which can be activated with a 3D Touch input on the left of the screen - and they will still be in memory, ready to go.