Japan's two largest cellular carriers, NTT DoCoMo and KDDI, are demonstrating this week some of their latest research into augmented reality systems.
Augmented reality fuses the real world with digital data and is seen as a potentially popular technology for future mobile phones.
NTT DoCoMo's system provides information on the phone's screen by overlaying it on a live image from the phone's camera.
The system polls the phone's GPS (Global Positioning System) sensor to find its location and grabs data from a digital compass in the phone to determine in which direction the user is facing. Armed with these two pieces of knowledge the system then interrogates a database to pull up information on attractions and landmarks nearby.
In a demonstration of the system at the Wireless Japan show in Tokyo the phone was simulated to be outside Tokyo's main railway station. Over a live video image from the phone's camera, which showed the station and nearby buildings, the AR browser added icons for restaurants. The distance to each restaurant was indicated by the size of the icon - smaller icons represented more distant restaurants - and the interface allowed the user to tap on an icon to get information about the particular eatery.
Because it was pulling information from a database it could indicate restaurants that were out of sight to the phone user, around a corner or behind a building. This could be potentially useful in finding a destination, especially in a city with many large buildings that obscure views.
After determining a place go the user needs to just hit a button and a route is mapped out on-screen.
The DoCoMo system also allows friends to see each others' positions on the AR browser, provided they have consented to release their information.
The prototype was running on an Android-based handset and NTT DoCoMo used the event to kick off a trial service of the AR system for 1,000 users. The trial runs over the next few months. Even in this trial phase it can be used anywhere in Japan because an extensive geo-tagged database of shops, banks, railway stations and other locations already exists for the country.
A short walk away, second-ranked carrier KDDI was demonstrating its prototype AR system on its stand. It ties GPS data together with information from the phone's motion sensor and polls a database of geo-tagged images.
KDDI's prototype doesn't provide a live image from the camera but has a simpler interface that shows images that have been taken nearby placed according to their distance and direction on a digital background.
The demonstration at the show pulled together shots of stands of other exhibitors and some of the shops in the area. This too enabled the user to figure out the direction of a destination whether it was within view or not.
On its own it's a fun system for a user that snaps a lot of images, but not particularly useful. However it becomes more useful if a family or group of people share their images or the phone is able to access a database of geo-tagged images from the Internet.
Both systems are prototypes and a launch date has not been determined.