TMCnet's Mae Kowalke reports today that U.K.-based Truphone has declared itself the world's first 4G network operator.

Truphone's software infrastructure lets users place calls and send SMS messages over Wi-Fi or cellular, switching to the most efficient network available at the time. The first handset to use the software is Nokia's E series, though the company says its aim is to make the solution available for many other devices before the end of the year.

For Truphone CEO James Tagg, it's all about helping users save money. "Wi-Fi telephony is going to change users' mobile phone experiences dramatically," he says. "I recently received a near-£700 mobile phone bill for a month that included one week spent on holiday in France -- 95 percent of this was roaming charges. Mobile VoIP technology, which is inherently much cheaper, would have virtually eliminated my roaming bill. Even £70 instead of £700 would have been acceptable, yet that sum is still three times the average revenue per user achieved by UK operators."

Sounds great -- though, as Mobile Magazine's Dave White points out, that whole 4G claim is a little iffy: "As for the 4G designation, that remains to be seen, mainly because the standards authors of the industry have yet to define specifically what 4G is," he writes.