Some of the games available seem designed to appeal to teens. Mr Collier showed off a virtual pet game from Panasonic, which is reminiscent of the tamagotchi craze.

The game uses the handset's camera to create food. When the pet is hungry, it shows a picture of a type of food like an apple.

You then have to take a picture of something red, which the phone interprets as an apple and feeds to your pet.

The game also lets you send food to a friend's pet via an infra-red connection.

Another virtual pet game uses a fingerprint scanner built into a handset to let your animal know that you are going to play with it, sending it into throes of joy.

Other games also make use of the camera on handsets. Mr Collier demonstrated a game which creates a fighting character based on your photo.

It interprets your image to give your character speed and power. You can then send this to a friend's mobile to do battle.

Another game uses a phone's microphone for educational purposes. The game is intended to help children with their pronunciation and works by comparing what they say with a sample on the handset.