Most analyst believe that Apple is releasing the iPhone 5S September this year, which suggests that production activities for the iOS 7-powered device have already started.

No official word on the matter is coming from the tech giant but the assessments were mainly based on information that Apple watchers claim were leaked out by manufacturing partners directly involve in building the iPhone 5 successor.

Rumours about the iPhone 5S abound yet this week three telling clues emerged, pointing to a strong likelihood that thousands of Chinese workers are now in the process of putting together the components that will power Apple's 2013 flagship into life.

They are listed below:

Volume production of iPhone 5S display is ongoing

Weibo, the popular micro-blogging site based in China, allowed a glimpse this week of a photo showing the purported iPhone 5S display sitting on a production line and seemingly geared for the next assembly process.

As in previous leaks, there is no way to verify the authenticity of the image though its appearance only fired up prevailing sentiments among the experts and Apple fans alike that D-Day is definitely near.

Apple supplies hints of confirmed and secret iPhone 5S features

Earlier this month Apple had unveiled the iOS 7, which in the process opened the gateway for keen Apple observers to pick out the possible iPhone and iPad killer features. Many of these device functionalities are readily noticeable but some remain hidden and will burst out only in time for the handset's release date.

One that merits attention is the new camera capability that according to Gotta Be Mobile is quite similar to an Android phone feature. The iPhone Cam, the same report said, will likely benefit from a new sensor that would the detection of facial expression. The native Android feature is intended to provide robust security for handsets running on Google's mobile platform. It is unclear for now, however, if Apple's version would serve the same purpose.

Apple badly needs a new iOS device

And it has to be the iPhone 5S, according to BGR News, citing the recent research note provided by Oppenheimer analyst Ittai Kidron. Nothing spectacular is happening on the Apple universe since the tech giant uncloaked the iPad 4 and the iPad Mini late last year, which somehow contributes to its slightly decreasing revenue, Mr Kidron.

While the general situation is far from alarming and iPhone models in current circulation are selling steadily, Apple needs to show off something solid to the market and consumers if only to provide "better visibility into the next product cycle."

Such move, he added, would prove "critical to drive (Apple) shares," which have been losing significant steam in the past few quarters. Apple, Mr Kidron said, is right on track to release the iPhone 5S in September, adding that "we see a larger iPhone (or the rumoured iPhone 6 as a CY14 reality."