USING THE Wi-fi capabilities of a Nokia Series 60 handset to provide low cost telephony is nothing new. But Defi Mobile reckons it has found a niche by pitching its own version of this service at business users.

Defi's chief USP is that it enables its subscribers to enjoy up to three 'virtual' telephone numbers. The differentiator here is that these numbers appear to callers like a fixed (land) line number rather than merely offering a different mobile phone number.

So if, for example, you were living in Spain but your clients were British, Defi can provide a London number which acts like a local call. While your Wi-fi connnected handset rings in Spain.

The business features of Defi's new service will make or break this offering. Facilities such as the ability to forward an incoming call to a colleague just as if the handset was connected to a switchboard.

What struck the INQ most about this service is its necessity to work through multiple Wi-fi networks – not just the network that belongs to the parent company.

Defi's CEO, Jeffrey Rice, told the INQ that Defi will be working through aggregators such as Devicescape to ensure that its subscribers get access in as many countries as possible. Presently it works in over 75.

Besides support for voicemail to email, Defi also enables subscribers to download their emails via Nokia's recently announced support for Microsoft Exchange Activesync.

Naturally Defi will be pitching its service as an excellent means of avoiding the vastly inflated charges operators currently levy for 'roaming' overseas.

The only snag here is that, at present, Defi doesn't support text (SMS). The company intends to charge subscribers a flat monthly fee of around £25 plus an additional £5 if you opt for three numbers.

Additionally, Defi also claims that it is looking to expand the range of handsets it can support beyond the N and E Series Nokias. RIM, Windows Mobile, UIQ and Apple were all mentioned.

The catch is that Defi is playing in an already very crowded market against established rivals like Truphone and the INQ wonders if its facilities will be sufficient to entice business users to join. µ