Apple's iPhone 5S could be getting a significant speed boost thanks to the rumoured A7 chip, which is reportedly 31 per cent faster than the iPhone 5's A6 processor.

Fox News's Clayton Morris has said on Twitter that the new iPhone's A7 chip is much faster than its predecessor, while 9To5Mac has said that the processor is 64-bit, which could mean a much smoother experience.

Morris on Sunday tweeted: "Sources are telling me the new iPhone's A7 chip is running at about 31% faster than A6. I'm hearing it's very fast."

He also tweeted: "I've also heard there's a separate chip devoted to motion tracking. Should be an interesting camera upgrade."

Also on Sunday, a report from 9To5Mac claimed that it has "heard claims that some of the iPhone 5S internal prototypes include 64-bit processors."

The report states that, should the iPhone 5S indeed ship with a 64-bit A7 processor, animations, transparencies and other iOS 7 graphics effects will appear smoother.

See: iPhone 5S preview

The iPad 5 is expected to feature the same A7 chip as the iPhone 5S, which could mean a better graphics performance for the tablet when it launches later this year.

It's possible that the 64-bit chips will be pushed back to a 2014 launch in a future iOS device, but that Apple has been testing the chips in this year's models ahead of a launch next year.

Respected analyst Ming-Chi Kuo has said that he expects Apple to make the transition to 64-bit processors, but that the move may not happen until the A8 processor is launched.

Apple is expected to launch its iPhone 5S, as well as a new, cheaper iPhone 5C, at a special event on 10 September.

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