By Jon Cronin BBC News business reporter

The craze for mobile phone downloads in Britain is growing

For some, arguably younger observers, he is a zany, anarchic and even cute mobile phone ringtone character.

For other, perhaps more seasoned observers, he is an incessantly annoying and mindless mobile fad.

But few could deny that the phenomenal success of Crazy Frog-themed ringtones reflects the growing strength of Britain's mobile phone download market.

Mobile phone users are expected to spend a total of �740m ($1.3bn) downloading ringtones, music, games and other content to their handsets this year, according to market analysts Mintel.

That represents a more than 18-fold increase on the �40m spent on downloads just three years ago, Mintel says.

The total number of mobile download sales is expected to reach 760 million this year, from just 30 million in 2002.

Clearly, the Crazy Frog is on to something.

'User-friendly'

"There is no denying that this sector has mushroomed," says Mintel consumer analyst Jenny Catlin.

"The user-friendly nature of downloading, which is really no more difficult or unfamiliar than texting, has helped foster a sense that receiving downloads are fun diversions."

The growing market for third generation (3G) mobile phones - which enable users to download better quality ringtones and games - is fuelling the boom "as is the popularity of ringtones, boosted by their integration with music singles in the UK charts", Ms Catlin says.

No-where is this more evident than with the recent success of Crazy Frog downloads.

Loved and loathed in equal measure, the ringtone character has propelled its owner Jamster to the top table of the UK's mobile download industry.

Introduced in November 2004, the Crazy Frog's garbled vocal sounds have spawned scores of ringtones, music and video downloads and screensavers.

In May this year, the Crazy Frog became the first mobile ringtone to make it to the top of the music charts with a version of Axel F, the theme to the Beverly Hills Cop films.

Junk texts

3G has increased the capacity and quality of what we can offer - it allows us to offer 300,000 tracks, everything from Bach to Bowie Vodafone

"It showed the way the borders of the music industry are crossing over with the mobile industry," says Jamster's Robert Swift.

"The most exciting thing about the mobile download market is that it is new and fresh. It's like the internet was a few years ago - people are just beginning to realise its potential."

While Jamster won't put a current figure on it, the Crazy Frog has earned its owner a small fortune. At the beginning of the year, before its chart success, Crazy Frog downloads were estimated to have made �10m.

However, with a target audience aged between 16 and 34, the company has faced criticism that it is encouraging users - many of them teenagers - to spend too much on downloads.

Many users also complain that they are bombarded with junk mobile texts, reverse-charged at premium rates, when they sign up for ringtones.

But Jamster says it is "consolidating and expanding its range of services", and ringtones are leading the way.

Gambling fever

Ringtones account for the largest share of the UK download market, with 33% of sales, according to Mintel. They are followed by games, with 26% of sales.

3G phones enable users to buy better quality downloads, faster

The rest of the market is made up of mobile phone screensavers (13%), gambling (9%), music (8%) and other content - from stocks and shares to pornography (11%).

While ringtones and games continue to make up the lion's share of the market, Mintel says the volume of gambling downloads is expected to grow by an estimated 367% this year.

A separate report by analysts Informa Telecoms in July suggested that the industry could be worth �24.6bn globally by 2010.

Such is the level of interest that major mobile operators including Vodafone, Orange and Hutchison Whampoa's 3 network are increasing the amount of download content they offer.

"It's a massive growth market," says Vodafone spokesman Ben Taylor.

"3G has increased the capacity and quality of what we can offer," he says. "It allows us to offer 300,000 tracks - everything from Bach to Bowie."

The UK mobile giant says its Vodafone Live service, which enables customers to download everything form clips of recent Ashes cricket tests to news bulletins, currently has 3.2 million users.

Rival operator 3 is aggressively pursuing the market for pop music and video downloads.

Older tastes

But not everybody is hooked to the mania for downloads, Mintel says.

Some 40% of those aged over 35 believe downloads are a waste of money, while a third of those aged over 55 say they are unsure about how to go about downloading a ringtone or game.

"It is possible that these people associate downloading with youth culture," says Mintel.

"The challenge facing the industry is to produce more substantial products that will attract older people, supplying products that can compete with other sophisticated leisure activities."

And that could mean - at least for some older users - a little less Crazy Frog.