Truphone company founder Ed Guy is one of his company’s best customers. “I’m a multiple device person. My cell phone doesn’t work in my house. So when I’d only need one device I’d have to carry two.”

Now he only carries one, thanks to UK-based Truphone’s long-awaited “mobile VoIP” for the Nokia N80, which was launched today. Currently the service is only available for Cingular and T-Mobile customers because Nokia doesn’t deliver WiFi-enabled phones for the other services.

Truphone’s “secret sauce” is simplicity.

You download the software by sending an SMS with the letters ‘TRU’ to a specified number. The phone is provisioned automatically and uses your existing address book.

There’s no sign-up charge or monthly fees. You only pay for calls outside the Truphone network. All you have to do is start making calls — no special numbers or key sequences. “It’s the type of thing your grandmother could use,” explains Guy.

When you dial a call Truphone first tries to route the call over the Internet. If that doesn’t work, the call is sent over the GSM cell phone network. There is reconfiguration that has to be done when you move between WiFi hotspots. But this job is still a one-key operation.

The obvious application for Truphone is cutting airtime charges, which add up very quickly for overseas calls. For example, GSM calls from the US to the UK are $0.34 per minute while the same call placed over the Truphone IP network is $0.024 a minute — less than a tenth the cost.

And there are other handy applications as well.

If you live in a place with poor cell coverage (like Ed Guy’s house in rural New Jersey) you don’t need another handset to make calls using your WiFi network. Another use is during a power outage. If you can find an operational hotspot, you can still make calls.

Now, some are saying that Truphone offers “seamless handoff” between cell and WiFi networks. That’s not quite true.

Yes, you don’t have to do anything but dial calls. But once the call is placed over one network it’s not going to move between the cell network and the WiFi network the way calls move from one area of cell coverage to another.

“We do have the technology for roaming between GSM and WiFi,” explains Guy, “but it hasn’t been deployed.” High battery power consumption is the issue, Guy says, and the company is working on a hand-off method that won’t interfere with battery life.

Truphone hopes to bring its dual-mode calling to more phones in the coming year, although Guy won’t commit to any dates. “We’re seeing a lot of user demand for VoIP-enabled phones,” says Guy. “It should promote the proliferation of hotspots.”

I was telling a friend of mine about “talk and send” SMS messages and his not-too-interested reply was “yeah, it’s called voicemail.”

The incremental ease of spoken SMS messages wasn’t something he was going to be writing home about. But he likes to idle away weekends fiddling with his network so he can turn on the living room TV from his computer, too. Added steps and complexity, if anything, stack up as positives on his value scale.

However, despite my friend’s dim view of it, VoIP and cell convergence via “talk and send” SMS seems to be picking up steam and uReach isn’t the only player out there. Last week San Jose, CA-based Pinger unveiled a public beta version of its instant voice messaging for cell phones.

The company was founded in late 2005 by former Handspring execs Greg Woock and Joe Sipher.

“There are synchronous ways to communicate with both your voice and text with voice phone or Skype calls and text instant messaging,” says Sipher. “Then there’s asynchronous text communication through e-mail. But there hadn’t been innovation in asynchronous voice communication. Sure, there’s voicemail, but it’s clunky and missing basic features like simply replying to a voice message without calling. We kept thinking, ‘Is there another way?’ That’s what we’re doing with Pinger. We’re making voice messages fast and easy, and we’re filling this gap for voice that was already filled with text.”

Pinger marries spoken messages with email. You get messages on your phone and in your email, letting you easily save - and forward - the new location of the softball game or the grandchildren’s first words. Another feature of the service is Web-based account management that can import contact lists from Outlook and other programs, although - alas - not Apple Mail.

Pinger’s service is carrier- and device-independent, which gives it an edge on uReach which is delivered through a service provider. Sign up on the website, create a contact list, add the Pinger number to your phone (put this on speed dial) and you’re in business.

To send a message, call the Pinger number, say the name of the person or group (which works like email groups) you want to send a message to - a real help when you’re driving - and say your message. Voila - it’s sent.

Pinger lets you send a message to anyone with an email address, although only other Pinger members can receive messages on their phones. Retrieval is flexible. Messages can be picked up by phone, email and the Pinger website. In addition, Pinger has an application for the Palm Treo that further simplifies use for that PDA.

Messages are announced on your cell phone with a text message. You call the number and the message plays - no menu, no prompts. To reply, simply press ‘1,’ speak your message and hang up. The message is sent.

Because Pinger also sends your messages to email, you can save them. If you pick up the messages on the website, you can annotate them - “Mark Foley drinks invite” - for future reference, say, when you’re called before the grand jury for a deposition.

Pricing for the service hasn’t been nailed down. The company says it will continue to offer a free service with a limited number of messages. Beta users who signed up before Oct. 1 get six months of free use. However, I signed up today and wasn’t asked for a credit card. Maybe they meant Nov. 1.

Text messaging sounds great. Just type in a quick message - “get milk” or “at mall” - and send. What could be easier? But in practice, trying to type on a 10-digit telephone keypad is an exercise in frustration.

“When you think about it, it’s surprising how non-mobile text messaging ends up being,” says Richard Stern, VP Marketing at Holmdel, NJ-based uReach. “You have to stop and type out the message.”

Making text messaging truly quick and mobile is the logic behind uReach’s SayText(tm) messaging service. It allows users to just ’say it on the go.’ The spoken message is then delivered just like SMS messages - something that is especially useful if you’re driving or you speak a language that doesn’t easily lend itself to a 10-digit keypad. Messages are received as SMS messages. Simply click to listen.

Saskatchewan telecom SaskTel recently chose SayText for its new Say and Send(tm) text messaging service. It’s part of the carrier’s strategy to stay ahead of the innovation curve for its 400,000 customers.

“We are continuously looking for the next new technology,” says SaskTel Director of Corporate Communications Michelle Englott. “This seemed like a convenient alternative to text messaging that our customers would be interested in.”

The beauty of the uReach approach is that unlike MMS (Multimedia Messaging Service) SayText uses the existing SMS infrastructure. That means service providers don’t have to invest in new infrastructure and consumers don’t have to buy new handsets. Instead, the service works seamlessly with existing mobile handsets.

Not quite 10 years old, uReach offers a SIP-based converged communications platform as both a managed service and licensed software. The company’s products include Enhanced Voice Messaging, Audio-SMS, Multimedia Messaging, Single Number Service which are available to both service providers and consumers.

uReach handles voice messaging for about 10 million customers worldwide, including SaskTel, SunRocket and about one third of Verizon’s customers. The company’s technology also underlies Bell Canada’s “Single Number Reach.” SayTalk has also been implemented by Singapore-based BubbleMotion in its BubbleTalk SMS service in Asia.

But SaskTel’s service is the first of its kind in North America. Other carriers likely to follow, though, and uReach’s Stern expects to be “making some announcements in 2007.”