Apple's next-generation iPhone, dubbed iPhone 5S, could be facing some delays due to production issues, an analyst has said, adding that the rumoured cheaper iPhone, which many are calling 'iPhone Lite', is still on track for a September release.

KGI Securities analyst Ming-Chi Kuo, who has correctly predicted Apple product launches in the past, has this week revealed that he expects Apple to face production challenges with its next iPhone.

See: Should I buy an iPhone 5 or wait for iPhone 5S, iPhone 6?

Apple Insider reports that Kuo has said that the so called iPhone 5S's availability will be "limited" when it launches in late September, but that supply of the new smartphone will improve in October or November.

The rumoured cheaper iPhone, dubbed iPhone Lite, could be ready to launch ahead of the iPhone 5S as it is easier to manufacture. He believes that it'll cost between $450 and $550 (£292 and £358), and that Apple will ship 26 million units of the device in 2013. That's below previous expectations of 30-40 million units.

The iPhone Lite will have "decent profitability, but at the cost of volume," Kuo says.

While Kuo didn't speak about the features he expects to see in the new iPhone models in his research note this week, he as previously repeatedly claimed that the next iPhone will have a fingerprint sensor beneath the home button for better security.

A report from DigiTimes earlier this month claimed that the fingerprint sensor could be the reason behind the alleged production challenges of the new iPhone.

He did say that the cheaper iPhone has "novel" new features, but didn't provide any further details.

In his research note this week, Kuo also predicted that Apple will launch a Haswell iMac in August, followed by a new MacBook Pro with Retina display lineup in September. As for the iPad mini 2, Kuo claimed that Apple will split the iPad mini line into two flavours: an iPad mini 2 with Retina display, and an iPad mini 2 budget model. Both will be held back until next spring, the analyst predicted.

See also:

iPhone 6 release date, rumours and leaked images

Profits dip again for Apple, while iPhone sales beat record

Apple hints at new products this year

Cut-rate iPhones? They're already here

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