Everyone likes to have the latest gadget. In fact, there are people whose lives revolve around getting the newest electronic toy, regardless of whether or not they need it. They have to have the biggest memory, the smallest buttons, the shiniest appearance. We have gadgets for playing music, gadgets for playing videos and toys that enable us to communicate with people across the globe in any number of ways.

Add to this list the 3G iPhone that is due to be released soon. There are going to be orders and queues around the block to snap up one of these little toys but buyers should ensure they read the small print first to check it fits in with their lifestyle and they should know of any hidden costs they are likely to incur.

Apple and O2 have come together in their use of unlimited download facilities and this has formed much of their marketing campaign. The latest 3G model will be available free on some O2 tariffs so thousands of people are expected to want to upgrade. One of the carrots that the duo like to advertise to entice customers to upgrade is the use of their unlimited data and wi-fi allowances. Mp3 music and videos are one of the most popular facilities that make or break a sale.

However, not all customers realise that this is only available while they use their phone in the UK. If you are a frequent overseas traveller and decide to download mp3 music while you are abroad, you will be facing a shocking bill on your return home. Many consumers have been caught out this way.

Once out of the UK, download charges shoot up massively. If you are still within Europe, the charge goes up to 3 pounds for each megabyte of data downloaded, anywhere else in the world will result in 6 pounds per megabyte. For the average BBC iPlayer programme, roughly 300Mb, this would come at a cost of 900 pounds if you were in France and 1,800 pounds if you downloading in the US!

Orange and T Mobile also charge staggering prices for mp3 music downloads, or any other type of download, outside of the UK with prices reaching 8 pounds per Mb. Having said that, the iPhone is likely to experience more downloads because customers like the large screen and it makes it easier to view programmes.

One of the biggest marketing strategies for the iPhone is that it doubles up as an mp3 player and this entices many people to buy the product. Mp3 music downloads are very popular among iPhone users but downloading one track outside of the UK could cost you as much as 18 pounds depending on where you were travelling - that's a lot more than buying a complete album on CD.

O2 say that they inform their customers if there are going to be extra charges for music downloads and programme downloads while abroad but services such as email updates use data services without first seeking permission for the extra charges from the user. For those who are frequent travellers and like the freedom of downloading what they want, when they want it then the best option is to acquire a bolt on package that will allow up to 50Mb for 50 pounds a month. This is ok for music downloads but is still going to get pricey for programmes and films.

Whether you are just popping off for a fortnights holiday or travel with work, then you should always check with your mobile phone company as to exactly what the charges will be, to prevent yourself coming back to massive bills.