Apple’s whizzy new 3G iPhone may boast speedier internet access than its predecessor but it could soon be outpaced by the rapid growth of free wi-fi hotspots.

With free wireless internet connections now being offered by everyone from McDonald’s to coach companies, some buyers may balk at upgrading to the new model when their current iPhone (not to mention many smartphones) already has a built-in wi-fi capability.

A report by Ofcom, the telecoms regulator, last year put the number of UK wi-fi hotspots at about 12,000. But Jiwire.com, an online directory of hotspots, claims the number has already more than doubled to about 26,800. Wi-fi can be faster than 3G, so, as it proliferates, time-sensitive mobile surfers may increasingly prefer it – especially as a growing number of hotspots are free of charge.

Wi-fi works independently of the network service on your phone, instead relying on antennae around the hotspot, which use radiowaves to transfer data at broadband speeds without cables.

McDonald’s has linked up with the Cloud, one of the largest providers of wi-fi hotspots in Britain, and is in the process of rolling out free wi-fi access across 1,200 of its restaurants. Coffee shops such as Starbucks have led the way in providing wi-fi hotspots (the Starbucks service is provided by T-mobile and is not free), and wi-fi can now be found in Borders bookshops, on some trains and coaches and in airports.

While some companies charge customers for wi-fi access, many simply see free wi-fi as a way to attract customers. The Oxford Tube bus company, for example, offers free wi-fi on all its coaches to London.

It isn’t only the commercial sector that is driving growth. Last year, Birmingham city council joined forces with BT to launch a project dubbed Birmingham Fiz (Fiz stands for free information zone) to offer wi-fi access to information about the area across one square mile of the city centre (full web access incurs a charge). Anyone with a wi-fi device can log on.

Westminster city council claims it will have the largest (paid-for) wi-fi zone in Europe when its service reaches full capacity later this year. Operated by BT, the zone will stretch for six square miles, offering wi-fi access all the way from Oxford Circus to Whitehall. BT is involved in similar city-centre schemes in Edinburgh, Newcastle, Leeds, Liverpool and Cardiff and plans to expands its Wireless City programme to Sheffield, Bristol, Nottingham, Portsmouth and Glasgow.

Another BT initiative, BT Fon, allows BT Broadband customers to share their home broadband connection with other users via wi-fi, and in return use other BT Fon users’ wi-fi links for free while out and about. BT claims it already has 100,000 subscribers. The service is now being extended to business users, who could use it to provide wi-fi access to customers.

One problem is locating a hotspot. The Hotspot Detector keyring (£14.99, see www.gadgetsquick.co.uk) might help. It claims to be able to detect hotspots within a range of 300ft, although it can’t tell you if they’re free. Alternatively, try searching on the jiwire site (www.jiwire.com), www.free-hotspot.com or www.cityspace.com.

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