If you are Nimbuzz, Truphone, Skype or one of the many other Mobile VoIP companies, here is some good news: A UK-based research group says the total number of mobile VoIP minutes will jump from 15 billion in 2010 to 470.6 billion by 2015, thanks to the proliferation of 3G and 4G networks. Juniper Research says the biggest boost will come from the U.S., which will account for 135 billion mobile VoIP minutes by 2015. Juniper recently forecasted that there will be 100 million mobile VoIP users by 2012.

“There are several flavours of mobile VoIP,” says Anthony Cox, Senior Analyst at Juniper Research, noting that operators fear losing traffic to Wi-Fi networks most: “Wi-Fi mobile VoIP is potentially the most damaging of all VoIP traffic, as it bypasses the mobile networks altogether,” he says. “We forecast that mobile VoIP over Wi-Fi will cost operators $5 billion globally by 2015.”

While the traffic minutes are going to grow, it is still difficult to see how much money these mobile upstarts will be able to make. In my opinion, the likely winner of the mobile VoIP sweepstakes is going to be Skype, mostly because it has the biggest network, which allows the service to offer easy in-network calling. As for the rest of them, well, maybe the carriers who hate them so much will end up buying them.

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In-Stat believes over half of those 288 million subscribers “will be associated with online mobile VoIP providers, under one-third will utilize mobile VoIP with 3G MVNOs or mobile operators, and 11 % with WiMAX/LTE operators.” Thanks to the increased availability of dual-mode phones, VoIP is becoming especially popular in the Asia-Pacific region, nudging the current market leader, Europe, aside. In the meantime, this move to mobile VoIP has prompted some to ask if we’re getting closer to an all-VoIP phone. I think so!

The carriers themselves are reluctantly embracing mobile VoIP, as we’ve previously noted. Today, Truphone teamed up with Australian mobile network operator Optus, for its Truphone Local Anywhere service. These kind of deals are going to become increasingly commonplace, taking annual sales of mobile VoIP applications to $35.2 billion by 2013, according to In-Stat. I wonder how that number would change if you included Skype.

Despite the big numbers, I bet making money isn’t going to be easy for mobile VoIP providers.

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For example, a U.S. resident could call home from the UK for 12 cents per minute on the Local Anywhere service. That same call for an AT&T customer with international roaming would cost nearly 10 times that amount. I see the benefit if you live in or travel to the initially supported countries — Truphone expects to expand the service this year across Europe, in Australia, Hong Kong and South Africa. So Truphone Local Anywhere makes financial sense — just like having a local Google Voice number geographically close to those who call you the most. But what about that MVNO business? How can Truphone succeed where so many before them have failed?

Let’s face it: With the notable exception of Virgin Mobile, very few mobile operators can even say “MVNO” without grimacing in pain. Odds are that this arrangement won’t be profitable in the traditional sense. Truphone isn’t looking to buy cellular service at wholesale and directly resell it at retail to eke out a small profit. Instead of that direct sell method, it appears to be one of indirect sales, in that Truphone hopes the arrangement will increase demand for its services and thus put money in the bank.

At the end of the day, it still looks like a standard yet slightly tweaked MVNO business model — and that’s not a model filled with optimism. In the meantime, it highlights one of the biggest challenges that Truphone and other competing services have to face: lack of control. The company may have an MVNO deal with Vodafone UK, but ultimately, who’s in control of the pipe, the data in it and pricing for it? Not Truphone.

This same lack of control is evident with the company’s VoIP offerings, too. To Truphone’s credit, the company earlier this week discussed its voice services over Wi-Fi vs. those over 3G and noted this very constraint. Karl Good, Truphone’s director of applications, put it this way:

“[U]nlike some of our competitors who have made VoIP calling available over 3G, we will not be doing so until we have developed a solution that will give our users a level of call quality that we are proud of.”

Without direct ownership and a stake in the level of call quality, Truphone simply can’t control the experience. And while I have high hopes for VoIP services — I use them myself on a daily basis — the ultimate issue is that these services are simply here ahead of their time. Voice is indeed a dying business in favor of data, as the numbers clearly show. But voice as data — on your pipe or someone else’s — is currently more advanced than the infrastructure on which it must rely. We’ll have to let history be the judge, of course, but voice isn’t the business I’d want to be in these days.

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Nimbuzz has certainly come a long way. At the time of its launch, almost three years ago, we were pretty critical of the VoIP-on-mobile service because it was a me-too offering that was quite a pain to use. A year-and-a-half later, Nimbuzz introduced a new meta client for the Symbian phones. It allowed you to sign into various IM clients. In addition, it allowed some basic VoIP calling, but it wasn’t really until they introduced the new iPhone client that Nimbuzz started to see some serious traction. My previous post gives a good overview of the Nimbuzz feature set.

The company just announced a super communication client for the iPhone that allows you to communicate in many different ways. For instance, you can make free calls over Wi-Fi to your IM buddies. You can also call folks on their landlines and mobile phones with SkypeOut using any one of Nimbuzz’s 10 VoIP partners including Gizmo5, Vyke, sipgate and A1 and, of course, Skype. This is a new feature in the service, and makes Skype In/Out Services more valuable.

These services also work over 3G and are described as “Nimbuzz Dial-Up VoIP” which essentially makes it possible to call others by dialing a local access number which then connects to anywhere in the world via Nimbuzz VoIP servers.

For the past month, I have been using the pre-release of NimbuzzOut on the iPhone to place calls to my far-flung group of friends and family. The calling prices are pretty good– about 8 cents a minute to India, 2 cents to the U.S., and 3 cents to the UK. If you look around, that is pretty much what you pay with most services — Skype is a bit more expensive.

The voice call quality is on par with Skype, which is still my communication method of choice for work-related calls. NimbuzzOut is dead simple to place calls: Just hit the call button, and you are good to go. You can, of course, use other calling services, but I don’t see any reason why considering Nimbuzz is offering good rates.

NimbuzzOut has a few features I personally like — you can natively use the phone client to buy additional minutes. I also like the fact that the client uses the native address book and doesn’t create a duplicate contact list. The Symbian client actually lets you edit, add and delete contacts from your address book.

There are a few things I don’t like: If you leave the notifications on, the client will run down your battery and leave the phone pretty useless. If you are using it on an iPhone, then you have to use the Wi-Fi connection, which makes me a tad upset because you can make Skype calls over 3G. You can make NimbuzzOut calls via 3G on Symbian phones, however.

Bottom line: If you are looking for a well-designed, easy-to-use, all-in-one messaging client that also makes cheap long-distance calls, then you don’t need to look any further than Nimbuzz. I have no qualms in recommending NimbuzzOut.

P.S. There is a reward for those who read the complete post. If you are among the first 50 people who send their name and Nimbuzz username to gigaom@nimbuzz.com, the company will give you a $25 NimbuzzOut credit.

Update: This offer is now closed. Thanks for participating.

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Nevertheless, this is still a wise strategy for Vonage to expand its customer base, as the company will now be able to lure people who don’t want to give up their landline phones but want the ability to make international calls using VoIP on their mobile phones.

A Vonage spokesman also said the company is working on “integrating communication products so that consumers can easily link home phones, cell phones and computers.” All of which is a significant shift from Vonage’s traditional business model, which until now has been based on replacing landline phones by selling special devices that use broadband networks to carry voice calls.

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These mobile versions of the Google Voice service will allow folks to not only manage their Google Voice connections –- to access and playback voice mails, send and receives SMS messages and read message transcripts — but also make local and long distance calls from mobile phones. The apps are fully integrated with each phone’s contacts, so you can call via Google Voice straight from your address book. This is how it works:

The mobile app for Google Voice uses the regular PSTN connection to place a call to Google Voice, which then places a call out to the person you need to reach. Since these calls (and SMS messages) originate from your Google Voice, they display your Google Voice number for the recipients. The service needs a data connection but it isn’t necessary to have a Wi-Fi connection to place and receive calls. The wireless number you buy from the cell phone company becomes less relevant.

The Google Voice app essentially reduces the cell phone carrier to a dumb pipe. While the BlackBerry application is interesting, it’s the Android application that shows that Google has bigger designs. I have been playing around with the Android App for about an hour or so and I can see the broader implications. When I was setting up the app, one of the options I was given: to make all calls through Google Voice. And that’s when I thought to myself: Oh! OH!

The app is so tightly enmeshed with Android OS and the address book and other apps, you hardly think that you’re using Google Voice. If Google bundles the Google Voice app with Android and sells it to makers of cheaper feature phones, it can start to insert itself between the consumers and wireless companies.

This “man in the middle” position is Google’s strength. The company has inserted itself between consumers and information via its search offering and profited handsomely from it. Why can’t it do the same with this voice offering? There is anecdotal evidence that some consumers might actually be happy paying for their mobile service by listening to advertisements.

To be sure, Google Voice isn’t the first such service. Truphone and a handful of other startups offer similar services, but Google’s sheer size is what makes this a pretty interesting move. They also have a mobile OS and connections with handset makers such as HTC to get serious traction. In this summer of a lot of hot air from Google — Google Wave and Google Chrome OS, for example — this is the first interesting product with larger implications. Suddenly the idea of Google as my phone company doesn’t sound so preposterous.

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In a previous post, I noted that the iPhone had turbocharged Truphone’s growth. Skype threatens to take some of that sizzle away. Skype’s entry into mobile VoIP will give everyone a heartache. Truphone and Nimbuzz are betting that by being über-communication clients, they can continue to thrive.

If the reaction to my post about Skype’s debut on iPhone is any indication, the world’s largest international voice service is going to become a major player in mobile VoIP pretty quickly. I’m pretty likely to switch to Skype, mostly because my SkypeIn number has a local number — a service Truphone doesn’t offer just yet.

BlackBerry owners in the U.S. will be happy to hear that Truphone is finally releasing Truphone Business, a BlackBerry application enabling business users to make international phone calls from their devices at wireline rates. You download the application. It works in the background. The minute you dial a number that’s international, Truphone intercepts the call and connects it to the international destination via the Truphone network. This doesn’t need Wi-Fi, unlike Truphone on Nokia and iPhone.

Having been an ardent fan of mobile VoIP startups (including Truphone), I am beginning to worry about the company now. We have seen this movie before — low prices, flat-rate pricing and price wars were all strategies used by desperate broadband voice startups that burned through millions of dollars in venture funding. Will history will repeat itself?

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A tipster — a very reliable one — tells me that Skype is almost ready to launch that iPhone version, perhaps as soon as next week. CTIA Wireless, a large mobile industry trade event, kicks off in Las Vegas next Wednesday, so perhaps the announcement will be made there. I am working on getting more details, as well as screenshots of the service. 

The biggest clue about Skype’s pending iPhone launch came when iSkoot decided to move on from its Skype-centric strategy. The company had been offering a client that allowed cell phone users to use Skype services. Skype already offers a Windows Mobile version of its client.

As I’ve said before, Skype will have to turn to mobile to keep its growth intact. In recent months, many services, among them Truphone and Nimbuzz, started supporting Skype in their communication clients. However, a standalone Skype client would get a lot of traction among the Skype faithful. In the meantime, I think Skype is slowly flexing its muscles and swatting away little VoIP players with some of its recent moves.

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These services also work over 3G and are described as “Nimbuzz Dial-Up VoIP” which essentially makes it possible to call others by dialing a local access number which then connects to anywhere in the world via Nimbuzz VoIP servers. Nimbuzz already allowed you to do social networking via its client. These services also work over iPod touch, but I haven’t yet tried that, and will do that later today. The new Nimbuzz user interface is much improved and easier to use. I think we have a new VoIP winner on the iPhone.

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In 2008, VoIP represented 26 percent of total fixed lines in Europe but brought in only 10 percent of the total fixed-line revenues. I bet a big chunk of the VoIP-related revenues are coming from VoIP-to-mobile phone calls. Mobile calls are seriously expensive in Europe, and as a result, any attempts by mobile VoIP companies such as Truphone have been met with resistance by the carriers.

Telegeography estimates that there were more than 35 million European households with VoIP service in 2008. That’s up from just 1.9 million VoIP lines in service in Europe in 2004. Telegeography also estimates that, during every quarter of 2008, more than 2 million homes signed up for VoIP service. Just to give context, in the U.S., we had about 19.4 million VoIP subscribers at the end of 2008. In 2004, there were 1.2 million VoIP lines. Telegeography analysts estimate that Europe will continue to exceed U.S. growth in VoIP lines.

Household penetration of VoIP telephony at mid-year 2008 ranged from slightly less than 50 percent in France to less than 3 percent in Spain, and annual subscriber growth rates ranged from 544 percent in Portugal to a comparatively anemic 13 percent in Norway.

One of the main reasons why France is so far ahead of rest of Europe is because of the presence of a truly disruptive company: Iliad, which offers a flat rate triple rate service under the brand Free. (Related article: Xavier Niel, France’s Broadband Maverick). Free’s offering forced everyone — including incumbent France Telecom — to offer similar, simpler triple-play plans, resulting in increased VoIP penetration.

Other related posts: In Europe, they like their VoIP (2007), VoIP growing really really fast in Europe (2008.)

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These startups are realizing that in order to make real money they would need to create billions of minutes in calls to off-net services. It is a game only the biggest -– Skype, for instance –- can play. And even then, making profits isn’t all that easy. More than a few startups have died trying to play the low-margin minutes game. (Related post: VoIP – Dead or Alive?)

For these three , the sheer size of their VC funding — over $100 million among the trio — provides a cushion while they plot their evolution.

Truphone, one of my favorite applications, has already gone from being just a mobile VoIP client to becoming an all-encompassing communications offering. By supporting Skype, Twitter and other communications services, Truphone is hoping to become the default (or at least the most used) communication application on the iPhone, which would allow it to generate more call-out minutes and also open up other e-commerce opportunities.

Mig33 is taking a different tack: going after digital goods for additional revenues. These digital goods would include virtual gifts, emoticons, and other means of self-expression. Such virtual gifts have been hugely popular in other online communities, such as virtual worlds and social networks. (Related Post: Venture Capital Loves Virtual.)

During our conversation, Steve Boom, a former Yahoo executive who recently took over as the chief executive of Burlingame, Calif.-based mig33, said that so far that company’s revenues have come from VoIP and digital goods, and that it will be focusing on the latter over the next six months. The company is looking to become cash-flow positive, and that is a big focus for Boom. Its application (and services) are extremely popular in Southern and Southeastern Asia, in addition to some parts of the developing world, where cheap calls are a lure for signing up new customers. (Related: Mad Money for mig33.)

Like its peers, San Francisco-based iSkoot has also tweaked its focus. So far, the company has been pushing a client-server solution that allowed folks to use Skype on their mobile phones. Its offering is the underpinning of the Skype service on 3, the UK-based 3G service provider owned by Hutchinson Wampoa. The company raised a whopping $19 million in Series C funding in November 2008.

The funds are to be used to develop a new platform for AT&T that would allow Ma Bell to offer iSkoot’s myriad services to its customers. For starters, iSkoot has released Notifier, a mobile application that allows folks to read RSS, and to interact with Facebook and Gmail on plain-vanilla mobile phones.

Company executives say that while iSkoot will continue to offer its Skype solution, the company has bigger ambitions, and Notifier is part of a bigger strategic shift by the company. (Related post: iSkoot Looks at a New Mobile Future) Who can blame them? It’s awfully hard to make a living selling a Skype solution to carriers who hate Skype to begin with.

Like mig33 and Truphone, iSkoot is making a smart move and losing its reliance on voice, a commodity business with razor-thin margins, and instead looking elsewhere for growth. Let’s hope by losing their (proverbial) voice, these three companies find something to sing about in the future.

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The company is now taking a big step toward becoming an all-encompassing service by announcing support for Skype and other instant messaging. If you have Truphone installed on your iPhone or iTouch you can make (and receive) Skype calls and send instant messages to other Skype users by downloading the updated software on Jan. 12. So far, accessing Skype on an iPhone/iTouch has been hard. (According to our commenters, you can use Fring for iPhone or Nimbuzz iPhone apps to access Skype.)

I had tried to wrestle Skype CEO Josh Silverman on when he was going to release a client, but failed to get an answer from him. So, from that perspective, this is a welcome upgrade by Truphone. The company is also adding support to other messaging services as well. You can also access Twitter using the Truphone client. The offering is exclusively for iPhone and iTouch for now. 

Geraldine Wilson, who was recently appointed as the chief executive of Truphone, told me in a conversation earlier today that Truphone wants to “offer our users a comprehensive communications experience. We started out as a voice app but now we are broadening it to other applications.”

By doing so, Wilson and Truphone founder James Tagg believe that they will give Truphone users a reason to stay insider the application longer, creating more opportunities to make phone calls and bringing in much-needed revenues. “In a mobile environment it is hard to switch between different applications, and that is why we are creating a single application environment,” Tagg says.

As we have noticed previously, iPhone and iTouch have been saviors for Truphone. Wilson told me that the company has more than 100,000 subscribers who use an iPhone, and iTouch has started to see an quick ramp as well. “Since the iPhone introduction, we are seeing our subscriber base double every month,” she said. In Fall 2008, I spoke with Truphone’s CTO, Alistair Campbell, who told me:

Truphone for iPhone now accounts for about one-half of the total number of Truphone users. And while he wouldn’t disclose the total number of downloads, he did say that the company is focusing more of its resources on Apple’s platform.

OK, now I have another reason to use Truphone.

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Skype Lite is the latest beta iteration of the former Skype for Mobile beta, which only supported a few smartphones such as the Nokia N95. Skype Lite supports more than 90 Java-capable cell phones (including some smartphones) that also have some basic web browser and data capabilities. An unlimited data plan is recommended.

This morning, Truphone also made an announcement about its ability to use the cellular network to make low-cost VoIP-enabled calls from and to the iPhone. With both announcements, it now appears that we will be seeing two major players in the low-cost international mobile conversation space.

There a few differences between the Skype and Truphone offerings: Skype, with over 30 million users daily, supports both voice and its own instant messaging conversations across a variety of mobile handsets. landline phones and PC platforms. Truphone supports voice and has shown support for messaging via traditional SMS services across mobile devices and landlines.

One caveat for both services: the low cost only applies when calling from your home country; otherwise you could invoke significant roaming charges.

Seems like Truphone has taken the leadership for low cost international calling on what is becoming a most popular smartphone (as well as several other smartphones). Does the combination of Truphone’s announcement and all this Skype beta activity portend Skype for iPhone too? It could be something for the new CTO and CSO to get behind.

Jim Courtney is an Associate Editor at Skype Journal.

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