Modern mobiles phones are overpriced and suffer from trying to be a jack-of-all-trades, according to the manufacturer of a new type of modular handset.

"You buy everything but the sink today," Zack Weisfeld, vice president of marketing at Modu Mobile, told vnunet.com.

"When you buy a phone you have everything crammed in and you're paying a pretty hefty price for all these functions and features when they're really not best-of-breed and are hard to use."

Weisfeld added that users are bound by contracts and expensive devices which they cannot change as often as they would like.

Dov Moran, chief executive of Modu Mobile, explained that people had turned to a single handset because they did not want to carry several devices at the same time.

"When you have one device you cannot get the best-of-breed and you are actually getting a device which is a combination of very mediocre subsystems," he told vnunet.com.

"It is not the best camera and it is not the best GPS and it is quite a lousy MP4 player and it is too small to have email and not convenient to watch video and it is too large to feel comfortable in your pocket."

Dov claimed that the idea behind Modu, a tiny mobile phone that slots into different 'jackets' to provide different functions, is to have a single device that could turn into whatever dedicated handset users needed it to be.

"We want to have one device, but one device that can be the best camera, with the best MP4 player and with the ability to do email or browsing, but its main functionality will be a camera," he said.

"Or it could be an MP4 player with a large display that would allow you to do wonderful browsing on the internet, but maybe doesn't have the best camera because it's not the most important thing for you."

Moran said that getting the best of everything in one device was not possible because of conflicts with size and features.

He claimed that the Modu device solved that problem. "You can really choose and have different bits at different times of the day," Moran said.

"During the day emails may be very important to you because you are an email person, or if you are a young student you want to have the best music.

"But maybe when you go to a movie in the evening you really don't intend to do email or to listen to music so the best thing is to have a very small device in your pocket to simply allow communication."

Weisfeld also questioned the credentials of fashion-branded handsets. "LG, Samsung and other companies have fashion-branded phones. There's a logo on the phone and it takes about 18 months to do that, which is not fashion," he said.

"The whole concept with Modu is to get the process with these big fashion companies where they create collections of Modu jackets that will fit their winter, summer, autumn collections with fabric, colours and expressions and really bring it to market in a very different way than it is today."