There's still 5 days until the third generation iPad goes on sale in Apple Stores, but two men have already lined up outside an Apple store in London after the tablet sold out online.

On Monday morning Zohaib and his friend Ali bought portable chairs and bags of supplies to start the long wait for the iPad store release, according to the Daily Mail.

Apple hasn't revealed the time the new iPad will go on sale on Friday, but with the initial stock sold out online, the lines are expected to be long.

Demand for the new tablet is off the charts, according to Apple, and shipments for current pre-orders will start shipping from March 19, three days after the tablets retail launch.

When the new iPad was unveiled last Wednesday, Apple promised its customers that pre-orders would arrive before the retail launch of the tablet on March 16. But popular demand for Apple's third generation tablet has caused severe delays in shipments, according to the company.

The quantity available for pre-order has been purchased, customers can continue to order online and receive an estimated delivery date, Trudy Muller told ABC News. Beginning Friday, March 16, the new iPad will be available for purchase at Apple's retail stores and select Apple authorized resellers on a first come, first-served basis.

Apple's new iPad has been heralded for its 2048 x 1536, 3.1 million pixel display, the most ever in a mobile device.

Until you see it you can't understand how amazing it is, said Phil Schiller in his presentation at Apple's media event in San Francisco last Wednesday. For the first time, an iPad has a higher resolution than the display screen used for the iPad presentation.

Schiller compared the new iPad to a 1080p, at 1920 x 1080 display, saying the new Retina Display 264ppi comes with 40 percent better color saturation than before.

With the new display, the iPad will seamlessly display crystal clear photos and movies. With the iCloud upgrade, iPad users will be able to re-download purchased movies that now support 1080p HD.

Other features of the new iPad include:

Processor: A5X quad-core processor touted as twice as fast and four times better performance than Tegra 3 chip.

Camera: 5-megapixel backside illuminated sensor on the back, 5-element lens, IR filter, and ISP built into the A5X chip.

Video: 1080p video recording.

Voice Dictation: Supports U.S. English, British, Australian, French, German and Japanese.

4G LTE: New iPad now has 21Mbps HSPA+ and DC-HSDPA at 42Mbps, with LTE taking the cake at 73Mbps. Verizon, Rogers, Bell, Telus and AT&T will be the LTE partners.

Battery Life: 10 hours of battery life still! 9 hours on 4G

Size: 9.4mm thin, weighing 1.4lbs.

Price: $499 for 16GB! 32GB is $599 and 64GB for $699.

Release Date: In stores March 16.