In August 2009 Wikitude previewed their new Wikitude Drive AR navigation system (which we covered in our news section here). Basically the merging of a TomTom with Augmented Reality, Wikitude Drive displays road directions on your camera screen along with optional integrated voice commands. It's a sensible idea (there's no need to buy a new monitor for it like you would a regular TomTom) but since using your phone whilst driving is illegal in the UK you'll either need an accommodating passenger or a dashboard mount to use it without fear of jail time.
Wikitude Drive works by accessing world wide navigational data in real-time from the net - although 'real-time' is a questionable term since most AR systems have a slight on-screen delay, meaning you have to turn your camera quite slowly or you get a jagged effect on the tags as they move in relation to you.

No doubt it all depends on the camera-type and internet connection speed of your mobile but presently a lot of AR software echoes the pre-broadband days where you had to wait eons for a page to load. It's obviously not nearly as bad as that but both Layar and Wikitude currently use limited data sets feeding into their browsers and are looking to the developer community to add more features, i.e. Make the system stronger and faster, in the same way broadband bettered dial-up.
While Layar and Wikitude are the frontrunners in the AR browser wars, they're not the only ones building a reputation in AR. The French company Total Immersion currently develop AR marketing promotions for Lego, BMW, Peugeot and have even made rides based on Hollywood movies. For The Dark Knight ride at the Six Flags theme park in New Jersey, clown masks were superimposed on rider's faces using an interactive mirror.

Tonchidot in Japan has created the Sekai Camera which allows users to tag their favourite restaurants and shops and though it's only available in Japan at the moment, Tonchidot plans to go international, which could spell tough competition for Wikitude and Layar. Meanwhile there are all manner of strange AR apps emerging: Earthmine lets users graffiti any skyscraper, wall or road via AR while companies like Int13 and Ogmento are designing portable AR games for children.
Which company will lead the way? Will it be Layar, Wikitude or an outsider we haven't even heard of yet? New AR companies seem to pop up just about every month so soon just about any application you can think of for work, rest or play will be on the market and we'll wonder how we ever survived without Augmented Reality in the palm of our hands.
Resources:
http://venturebeat.com/2009/07/08/layar-wikitude-duel-to-become-augmented-reality-browser-of-choice/
http://games.venturebeat.com/2008/08/05/total-immersion-blurs-real-and-virtual-in-theme-parks/