The latest from the iPhone 5S and iPhone 5C rumour mill

Eager Apple fanboys are counting down the hours until tomorrow, when Apple is set to unveil its latest iPhone, and as ever on the run up to the launch, the rumour mill has gone into overdrive.

Last Tuesday, Apple sent out colourful invites for the 10 September event at the company's headquarters in Cupertino, a big hint that the iPhone maker plans to unveil a new line of multi-hued smartphones that breaks away from its traditional black-and-white colour scheme.

After the Cupertino event wraps up, Apple will host a second iPhone shindig in China on 11 September, where it will likely make some region-specific announcements.

In recent weeks, rumours have been swirling that the iPhone 5S will come in gold and graphite colour options, alongside the existing white and black models. Besides that, Apple is expected to unveil the low cost iPhone 5C, which may be priced at around $399 (£255) off-contract and come with at least five multi-coloured back enclosures, including blue, red, yellow, green, and white.

So here’s our round-up of the latest rumours to emerge last week, ahead of Apple’s event which kicks off at 18:00 tomorrow – and naturally we’ll be there covering all the details.

Multi-coloured iPhone 5Cs

At the start of the month, 9to5Mac spotted some images of what appear to be new handsets labelled "iPhone 5C" and sporting pink or red cases with matching wallpaper.

The photos first appeared on the Chinese language site iApps.im and purport to show a lower priced, plastic-backed, sans-Siri iPhone, which will come in a rainbow of colours.

Fingerprint sensor

Photos posted online last week reinforce previous rumours that the next iPhone will come with biometric fingerprint scanning technology. Last Tuesday, the French site Nowhereelse.fr published images it reportedly obtained from a "mole" purporting to show a new home button cable part that may support a fingerprint sensor. As MacRumors explained, the part contains a new square surface and several other components not found in the iPhone 5 that may be related to fingerprint sensor functionality.

Bigger screens

The iPhone 5 sports a 4in screen, which is small compared to many other smartphones on the market. But Apple is reportedly looking to find out if bigger really is better. As we reported last Friday, according to The Wall Street Journal, the tech giant may be planning to offer iPhones with screens as big as 6in.

Don't expect to see a larger screen on the phone released tomorrow, though. The company just began testing larger iPhone screens, and the display sizes on the iPhones Cupertino is planning to show off tomorrow are not expected to change.

China Mobile

The fact that Apple is holding what's likely to be an iPhone unveiling in China so close on the heels of its US event lends some credibility to one rumour that has been swirling in recent months. According to reports, Apple plans to strike a deal with China Mobile, the world's largest cell phone carrier with an estimated 740 million subscribers. The iPhone maker already sells its smartphones through China's two other state-run telecoms, China Telecom and China Unicom, but courting China Mobile is important since the iPhone is reportedly lagging behind Samsung's smartphones in China.

DoCoMo deal

In addition to China Mobile, Apple is also finalising an agreement to offer the iPhone through Japan's largest carrier, NTT DoCoMo, according to a report from Bloomberg. Apple already offers the iPhone through SoftBank and KDDI, the next two largest mobile carriers in Japan, but adding DoCoMo would be a huge win for the company, which is aiming to reach new customers to grow its sales and profit.

Got your watch set to count down mode ahead of Apple's big 10 September unveiling? Follow our live updating coverage of the iPhone 5S and iPhone 5C launch for all the latest news and analysis and be sure to join us on the day!