The ability to make free mobile phone calls to anywhere in the world at any time of day sounds tempting, if unlikely. But last week the UK mobile phone network operator 3 Mobile declared this a reality with great fanfare when it launched a new phone in partnership with internet-based telephony provider Skype.

It’s not entirely free, though. To get hold of the modest-looking handset you must first sign up to a mobile phone contract starting from £12 a month, while pay-as-you-go owners have to cough up an initial £50 and then add £10 a month of credit for calls to a landline or standard mobile phone.

Calls are free provided both you and the person being called are signed up to the Skype service. You do this either by visiting the Skype website or using the handset itself, and it costs nothing. The snag comes if you want to call a nonSkype user; it’s then you are charged for the call at a rate that’s dependent on the tariff you’ve selected.

To make a Skype call, you press a button on the phone that shows a list of Skype contacts to whom you speak for free if they own the same handset or are using a computer or other Skype-enabled equipment.

The phone uses its integrated data connection to set up the Skype call. The voice signal is sent over 3 Mobile’s standard cellular network. Once it reaches the company’s main hub it is relayed to their Skype handset or pinged over the internet to the recipient’s computer. According to Jupiter Research, the telecoms analyst, about one in 10 UK consumers with an internet connection made use of Skype in the three months prior to last April. That’s a fair number of people and a figure large enough to suggest that Skype is developing a solid customer base.

The biggest drawback is that you must switch to the 3 Mobile phone network, whose signal coverage is regarded as patchier than that of rivals. Coverage has improved of late, but a Which? customer satisfaction survey published in September still rated 3 Mobile the worst of the big five UK mobile-phone networks.

The company also suffers terribly from “churn”, a term that describes footloose customers dumping one provider in favour of another. Because of this, and despite the undoubted benefits for some users, the marketing whiffs a little of desperation, wooing new customers and holding on to them to sell them 3 Mobile’s pricey music downloads or video services.

And that’s a shame, because in brief tests of this new handset we found the quality of call to a computer was decent, albeit noticeably inferior to a call between landlines and more akin to a slightly iffy mobile phone connection. In truth, all internet-based telephone services are susceptible to the vagaries of the online world.

“If you are phoning another Skype handset the call’s voice quality will be equivalent to that of a standard phone connection,” said John Yates, technical manager of Hutchinson Whampoa, 3 Mobile’s parent company. “The only difference is a slightly longer [10sec] connection time.”

So is it worth ditching your mobile phone for a Skype handset? Many mobile phone tariffs include the offer of free calls, though usually only domestic ones, so the principal advantage of this Skype phone deal lies with the ability to hold long peak-hour chats with people in other lands.

Although the handset can call standard mobiles or landlines it doesn’t employ the cheap Skype-out service to do so, but instead works as a normal mobile phone. “This is not the full Skype experience – more ‘Skype-lite’,” warns Ian Fogg of Jupiter Research. Also keep it in mind the Skype service is already available on 3 Mobile’s premium-priced X-Series handsets, so the new set isn’t necessary, but it is cheaper and easier to use.

Yates admits: “If the Skype phone encourages people to come to us in order to use free services and they go on to try other ones, that is a good thing. The more the merrier.”

gear@sunday-times.co.uk

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