1. Force Touch – Apple’s biggest risk will be altering the iOS input method for the first time. Force Touch will bring additional controls via a strong press of the screen. This must prove intuitive or Apple will damage the famously simple usability of iOS.

2. 12 MP Rear Camera With 4K Video – after multiple generations using an 8MP camera, Apple will make a 50% sensor increase for the iPhone 6S and iPhone 6S Plus. The increased sensor size will bring greater detail to shots and enable video to be shot in 4K ‘Ultra HD’ for the first time.

3. 5MP Front Camera With 1080p Video – equally important for our selfie obsessed world is Apple will finally give the iPhone’s neglected front camera a major upgrade with a 400% increase to 5 megapixels. This will also enable 1080p ‘Full HD’ video recording.

4. Size Increase - Breaking with tradition, the new iPhones will be fatter than their previous generation and gain some weight. Is this a problem? Not given this is to accommodate the Force Touch sensor.

5. Stronger Chassis – Another key factor in the positive aspect to the weight gain of the iPhone 6S and iPhone 6S Plus will be a move to stronger 7000 Series Aluminium. A leaked chassis has already been tested on video showing massive strength improvements  .

6. Apple A9 Chipset - iPhones get faster every year and the new models will be no exception. The iPhone 6S and iPhone 6S Plus will get Apple’s next generation A9 chipset for increased CPU and GPU performance.

7. Increased RAM - while the A9 is expected to offer only relatively modest improvements compared to the A8x seen in the iPad Air 2 last year, arguably more crucial will be the new iPhones’ doubling of RAM to 2GB of LPDDR4. The Air 2 jumped to 2GB last year and it will be crucial to the enhanced multitasking capabilities which will come with the new iPhones.

8. Upgraded Touch ID - with Samsung and others now offering fast, accurate fingerprint sensors, Apple will look to step ahead with a new generation of Touch ID which it believes will be the fastest and most accurate fingerprint sensor on the market.

9. Enhanced voice calls – Apple will add an extra microphone beside the speakers in the iPhone 6S and iPhone 6S Plus to make voice calls clearer and to take full advantage of growing support for HD calling.

10. Sapphire Lens cover - This will depend on whether Apple can solve production issues, but the expectation is the new iPhones will sport sapphire camera lenses to offer greater scratch resistance. Apple has used sapphire in the iPhone home button for some time.

11. Rose Gold – To make the Apple Watch, the iPhone 6S and iPhone 6S Plus will be offered in an additional rose gold finish.