Augmented reality on the iPhone is really taking off. A load of apps have already surfaced on Apple's App Store, while many more are in the pipeline.

The reason? Everybody was waiting. Waiting for Apple to update the iPhone software to 3.1. That gives developers the ability to lay data over the camera viewer, and these apps can take full advantage of this new capability.

However, you will need an iPhone 3GS with its extra graphics grunt to take advantage of these apps - the old-skool hardware in the 3G just won't do. Right, on with the list. And we've even got video of all the apps in action, too.

1. Bionic Eye

By Presselite, this clever app makes use of the iPhone's camera to bring alive the area you are in like never before. It offers up a whole host of visual reference points (10,000 if you live in the US) like your nearest fast-food chain, coffee shop or underground stop, all with 360-degree functionality. It's available now from the App Store – check out our hands-on.

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2. TwittARound

This cool app isn't available from the UK App Store as yet, but it sure looks like fun, if limited in usefulness – you can 'see' the direction and distance of people currently tweeting. Pretty clever stuff – this video is definitely worth a peek.

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3. SREngine

Just at the prototype stage, this app is designed to recognise objects, such as the front of a house, shop or something on the street. The application can then offer you different actions depending on the type of object. For example, point the iPhone at a shop and it will tell you what it sells and give you its phone number.

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4. Nearest Tube

Acrossair, the dev behind the TVGuide.co.uk app, has produced various apps for underground systems in different cities. Nearest Tube is a £1.19 app for Londoners to see the direction of tube stations around them. On loading the app, you will see the Tube lines displayed in their respective colours and holding the phone up will show you the distance to the station and what lines they serve. Other cities are available, while the company also produces Nearest Places for the same price, enabling you to locate places of interest such as coffee houses, bars or banks.

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5. TAT Augmented ID

This one is very cool. In fact, it's our favourite. It utilises the clever Flickr face recognition tech from the guys at Polar Rose to recognise a face and surround them with their social networking profiles from sites like Facebook, Twitter and Last.fm. Really great stuff - though probably not great for anybody trying to keep their identity secret.

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6. Worksnug

This mobile working application from Worksnug uses the iPhone 3GS compass, camera and GPS to give you information about the best public places to park your laptop and work. The forthcoming app will overlay information about venues such as coffee houses, including a score based on availability of Wi-Fi, power sockets and even the quality of the coffee. Richard Leyland, founder of Worksnug, even told TechRadar that he wants it to be free. It'll launch in London first with San Francisco and other cities to follow.

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7. ARf

A prototype that's been around for a while, this augmented reality pet game enables you to hover your iPhone above specific cards and objects to do different things with your pet. Limited in use, but interesting nonetheless.

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8. Wikitude AR Travel Guide

Not yet available on iPhone, but currently on Android, the Wikitude AR mobile travel guide enables you to search for Wikipedia entries near your current location and show them on your screen as you pan around. Not quite as useful as being able to see the location of a nearby coffee house, but still worthwhile.

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Liked this? Then check out Virtual reality goes High Definition

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