nce upon a time, mobile phones were designed simply for making telephone calls. Not any more. Today, many of the latest handsets come with MP3 player, television, and computing or even camcorder facilities.
But in spite of all the flashy extras, most people still don't use their phone for much more than making calls and texts. Mobile internet, for example, has been around for several years, but has not yet taken off in any serious way. Similarly, mobile television has got off to a slow start. One reason for the slow take-up is that many people assume using the latest technology will be prohibitively expensive.
What they don't realise is that most of these new services are free or cost very little - the mobile phone networks are so desperate to get people using their services, they're practically giving them away.
Using the internet on your mobile phone can be a costly pastime. However, for most contract customers, the costs are fairly low, or even non-existent if all you want to do is to browse basic sites.
Vodafone's internet portal - Vodafone Live - is free to use for both contract and Pay As You Go (PAYG) customers, as long as you resist the temptation to download anything. If you just want to catch up on the news, football results or weather, and you stay within the Vodafone Live portal, browsing won't cost you a penny.
The costs begin once you leave the sanctuary of Vodafone Live. Browsing the rest of the web is charged by the megabyte - £2.50 for contract customers and a hefty £7.50 for those on PAYG. It's a similar story across most other networks - and is one of the main reasons many people do not use the web more freely on their phones.
O2 gives you the first 100kb free and then starts charging at a rate of £3 a megabyte; T-mobile charges 73p a megabyte on its standard packages; while Orange gives you 4mb free and charges £1 a megabyte thereafter.
But what does it all mean? If you ask the phone companies how much browsing you can do for 1mb, you'll get all sorts of different answers. Although they say the average page is 10-15kb - so 1mb gets you 66 to 100 pages - they always add, as a caveat, the warning that some sites use more.
The networks are beginning to tackle this by offering fixed fees for unlimited browsing. T-mobile now charges £7.50 a month for unlimited access - on top of your regular monthly tariff - while Virgin Mobile charges 30p a day.
This week, Three launched an innovative package, known as X-Series, which will not only allow unlimited browsing for as little as £5 a month, but will also potentially allow users to access their home TV channels and home computers through their phone.
However, Three has had more than its fair share of technical glitches in the past, so it may be worth waiting a few months before you jump in.
If internet speed is a priority, T-mobile and Vodafone now both offer new faster broadband, known as HSDPA - although you'll need the right kind of phone to take advantage.
Robin O'Kelly of T-mobile says HSDPA can currently offer speeds of almost 2mb, which is as good as many people's home broadband packages. The phones can also double up as portable modems for your laptop, giving you broadband access on your PC wherever you go.
Networks have been debating whether to plough their resources into mobile TV for some time, but until recently have held back. Mike Short, of O2, says his network did the country's largest trial of the service a year ago - giving TV to some 375,000 customers.
Its conclusion, however, was that while there was an appetite for the service, the technology wasn't yet there. Short says that the 3G network was always only designed to accommodate one-to-one connections, and really struggles when companies try to let multiple users access one source.
In recent months, its rivals have rolled out services - some simply using the 3G network, and others coming up with new ways to provide a better connection.
For example, Virgin Mobile launched live TV using the DAB digital radio network in October. Paul Coombes, the company's product manager, says this currently allows users to watch BBC1, ITV1, E4 and ITV News - all live, and formatted to fit your phone. Channel 4 is soon to be added to the package. This service is free for all contract customers (as long as you have the phone to support it), and costs £5 a month for PAYG customers.
Three's X-Series allows you to watch all the channels on your home TV. However, as well as needing the right phone, you need to splash out an extra £99 on buying a "Slingbox", the piece of technology that facilitates the transmission. This is operated over the normal 3G network. It remains too early to say whether the package will live up to its billing.
Vodafone has taken a different approach to TV. Spokesman Ben Taylor says the company is not convinced that people want to watch long segments of live TV. As a result, it offers five-minute edited highlights of shows from various Sky channels, as well as offering a live feed to Sky News and Sky Sports. Its packages cost between £5 and £10 per month.
Chris Frost of the comparison website Uswitch.com points out that one of the main drawbacks of mobile TV is that your phone battery power gets eaten up quickly.
"The size and quality of the screen on your phone may hamper your quality as well," he says. "Batteries quickly run out of juice when playing back power hungry video services." Both problems may prove a frustration, especially if you're watching for extended periods.
Mobile phone companies have long been claiming that instant messaging has the potential to become as big as texting. It's already popular on computers, and if you need to have a quick conversation with someone at a time when it's not convenient to make a call, it can prove a quicker way of getting things done.
Three has led the way with IM, as it's known in the industry, making it free for all its users earlier this year. The rest of the industry tends to charge by the megabyte - once again making it difficult for users to know exactly how much they are spending. Once it becomes free for all, it is likely to have a much greater take-up.
Anthony Ball, a director at comparison site One-Compare.com, warns that for the moment, most people will be better off going for a tariff that best suits their calling needs. "With phones containing so many features, consumers may become overwhelmed by the choice and neglect to use a lot of them," he says.