A HAMPSHIRE mobile phone services company founded with £100 four years ago is now the world's biggest on- line ringtone retailer.

And the Symbios Group claims it is on the verge of unveiling the technology to power the next generation of call alerts which will see users fashioning their own ringtones out of their favourite music.

Called Realtone Mix, the revolutionary software allows people to log on to a website with their phone, pick a section of their favourite piece of music and loop it to form a unique ringtone.

The service is expected to cost around £3 a time.

"What we have done is build the ringtone equivalent of Itunes," said Symbios co-founder Martin Montague, comparing his development with the Apple Macintosh Ipod music-downloading phenomenon.

"Say you liked a certain bar of a Robbie Williams song, you could have that playing repeatedly over your mobile phone.

"Music on the move is definitely the way the market is going. The potential for this is huge."

The big business advantage of Realtone Mix is that it opens up the global market of 232 million mobile phones equipped with WAP that can use the software.

Much of that market, which is forecast to swell to 374 million by the end of next year, was previously out of reach due to technical and billing difficulties solved by the new software.

The brainchild of brothers Martin, 31, and Steve, 41, Segensworth-based Symbios employs 19 people and has more than 80 million unique visitors to its 1,000 ringtone websites. Ringtones are its core business but Symbios is also a leader in the controversial and emerging market of mobile phone adult content.

All that remains for Symbios is to seal a deal with some of the major music companies - smaller industry players have already signed up and the company has a crunch meeting with EMI and Chrysalis Records tomorrow.

"If we can get the music industry on board, and we have already got some, this will be the biggest thing ever to hit mobile phones," said Martin.