Apple is all set for a Q3 2013 release of the iPhone 5S and its budget version, with the latter likely to carry a price tag of around $US329, new reports said.

Production of the refreshed iPhone 5 is reported to commence in full swing by May 2013, according to Taiwan-based DigiTimes. The publication added that all iPhone components that will make up the final iPhone 5S build will reach Apple's manufacturing partners at about the same time.

That should mean Foxconn and other minor iPhone 5S builders will have ample time to meet the tech giant's calendar of putting the new smartphone to global store shelves by August at the latest.

However, reports are persistent that Apple intends to release the iPhone 5S no later than June or a few moths after the commercial release of its closest handset rival - Samsung's Galaxy S4 that was unveiled last week.

As if affirming the earlier reports, DigiTimes also indicated that consumers will get incremental upgrades on the iPhone 5S and not a major bump up that many had expected.

"The iPhone 5S is expected to feature a higher-end processor as well as higher-megapixel camera modules," the same report said.

DigiTimes mentioned too that "Apple plans to release an iPhone model using plastic chassis to push its global smartphone market share."

The basic configuration of the same handset is 3G-capable with 8GB of built-in memory and will start selling in emerging markets at an average price of $US329, according to a report by ValueWalk.com.

With the price mark, Apple is expected to boost its corporate gross by 38 per cent or additional revenues of up to $US21 billion by financial year 2014-2015, the same report said, citing the analysis furnished by Credit Suisse.

Apparently, Credit Suisse believes that Apple will profit tremendously from the expected uptick sales of the cheaper iPhone edition in lucrative markets like China, Brazil, India and Russia.

But the report noted that Apple will likely witness too some form of cannibalisation for the regular iPhone, replicating the scenario seen with the 9.7-inch iPad in the immediate months after the iPad Mini was rolled out.