News: Apple has applied for a patent for a slap bracelet with a video display that could be a blueprint for its much-anticipated "iWatch" concept.

The US Patent & Trademark Office today published details of the application for a "bi-stable spring with flexible display" together with images of a product that could be worn on the wrist or elsewhere on the body. The patent was filed on 17 August 2011.

The product, containing a strip of flexible steel, would wrap around the user's wrist and feature a continuous digital display along its length.

"The wearable accessory device includes a flexible display coupled to a bi-stable spring," says Apple's patent description. "Coupling the display to the bi-stable spring allows the accessory device to be easily worn in a number of convenient locations."

An "end detection mechanism" would allow digital information to be displayed seamlessly around the wrist, allowing video "to smoothly continue across a portion of the wearable video device where the flexible display overlaps itself."

The device is designed to be used in conjunction with a "portable electronic device" - a rectangular object with its own video screen that could either be flexible or stiff. The two devices would communicate wirelessly.

Rumours have been circulating since last month that Apple plans to release a wearable smartwatch - dubbed the "iWatch" - that would work in conjunction with an iPhone.

Wearable technology is expected to become a huge industry as features contained in today's smartphones migrate to devices worn on the wrist, face or skin.

Earlier today Google unveiled a video showcasing its Google Glass headset,  that will give users the ability to send and receive messages, take pictures and search the web without using their hands.

Last year John Hanke, head of Google Maps, told Dezeen that wearable gadgets may soon make phones redundant.

"I think the general idea is that the phone as an object kind of disappears," said Hanke. "People are working on skin sensors and other ways of transmitting information to us in a way that's passive and that doesn't require us to divert our attention in the way that we do with the phone today."

Last year the Pebble smart watch concept became the most-funded Kickstarter project of all time, raising $10,266,845 in one month. The product went into production last month.

Other wearable devices released recently include the Nike+ FuelBand, which is worn on the wrist and tracks the users' physical activity, and the Jawbone Up, a similar device designed by Yves Behar.

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