Apple has finally ended speculation about the unveiling of its much-anticipated new iPhone model, sending out invites yesterday for an event on 4 October (next Tuesday) taking place at its HQ in Cupertino, California.

However, while Apple’s invitation (pictured) offered an opportunity to “talk iPhone” it did not explicitly mention the new iPhone 5. This ambiguity has led to media speculation that Apple may unveil not just a new model, but several new versions of the current one (iPhone 4), possibly one designed for the Chinese market or a new low-cost version.

On the hardware side, iPhone 5 is expected to feature incremental upgrades in processing power, camera quality and – possibly – a slightly larger screen size. However, it is thought unlikely that it will support new 4G technologies such as LTE.

It will run Apple’s new iOS5 software, which includes new cloud and messaging features. According to sources, iPhone 5 will begin shipping within a few weeks of the announcement amid reports that many operators are already talking pre-orders. 

Next week’s event will also be notable for the being the first Apple media event overseen by the firm’s new CEO Tim Cook, who succeeded Apple's legendary co-founder Steve Jobs last month.