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Mobile VoIP apps have really blossomed this year. These apps, which deliver voice calls over IP to a mobile handset over a WiFi or a cellular network (3G, etc), let you make make cheap or free mobile calls, which can save you tons on your monthly bills in these “jobless recovery” times.

But with so many new players on the market, you may have a hard time choosing. I tend to prefer the ones that provide a single application environment for users — not just a call utility, but a full communication ecosystem. The apps that I have shortlisted as my favorites are Fring, Nimbuzz, Skype, Truphone and Vopium. There are others in this space ( like Jajah, Rebtel and Gizmo), but I will be focusing on these five for now.

fringMy first choice is Fring. Fring lets you access and interact with a variety of communication services. It’s extremely easy to download (SMS, WAP or via PC) and is compatible with multiple platforms such as Symbian 8, 9.1, 9.2, iPhone, Windows Mobile 5 & 6, UIQ handsets and, yes, Android phones, too!

Once installed, you can interact with friends on social communities such as Skype, MSN Messenger, Google Talk, ICQ, SIP, Twitter, Yahoo IM, and AIM and can create a buddy list (“Fringfriends”) from these contacts. However, it doesn’t support Facebook and Myspace at this time.

Users can make and receive calls using Wifi or the cellular data plan to all of your Fring contacts for free. You can instant message them and find out what they are up to by checking their statuses. You can also find their actual locations (now that’s freaky!).

Fring also lets you make local and international calls to landline and regular cell numbers using your SkypeOut/SkypeIn account or almost any VoIP service.

Video calls anyone? Can do! Fring recently announced its new feature of making and receiving video calls with your mobile for free. No other platform I know of currently offers this game-changing functionality. The camera location on most mobile devices, including the iPhone, is not well suited for this, but it’s still a an amazing feature to have. Just a caveat: Fring video is only currently supported on Nokia touch (such as X6, N97 mini,N97, 5800), N95, N95 8G and N82 devices. For music lovers, Fring also offers a add on, which you can share with your friends.

Fring is also one of the applications that has an Android-specific version (in addition to an iPhone one), which supports the full Skype version. Since Skype’s own mobile app currently doesn’t support this full Skype for Android, Fring really takes the upper hand here.

One last thing for the techies out there, Fring also have an API platform for third-party developers to write add-ons against. So if you’re itching to give it a try and write something cool, check it out at

NimbuzzNimbuzz is another mover and shaker in this mobile voip space. Similar to Fring, the Nimbuzz application is easy to download and install. It lets you easily create a buddy list and interact with your contacts from Skype, Windows Live Messenger (MSN), Yahoo Messenger, ICQ, AIM, GoogleTalk, etc. It also extends its feelers into social networking platforms such as Facebook and MySpace, which not a lot of apps offer yet (not even Fring), giving itself an edge.

You can call anyone from your list, instant message them and send text messages and files for free, as long as your friends have Nimbuzz installed or if they are using MSN, Skype or Google Talk applications.

The calling option plan is also very similar to Fring and other apps in this space. Calls to and from buddies and social network friends are free (whether local or international), and you can take advantage of your Skype credit account. Nimbuzz also offers a Nimbuzz! Out calling plan, which is an interesting option, however the calling rates for Skype are more affordable.

The app has two very appealing features: First, the buzz option. If you want to talk or chat with one of your friends and they aren’t online, you can “BUZZ” them. When “BUZZED” a user’s phone will ring once or twice and display the Nimbuzz ID of the person trying to reach them. Pretty nifty. Second is its support for Android. It’s rolled out free mobile VoIP calls to Android users.

With its recent release, Nimbuzz lets you send photos, videos, voice messages and music directly to all your online friends for free! Even better, all your received files will be stored online, and you can access them whenever you sign in via your mobile or PC/Mac

Overall, Nimbuzz’s user interface could use a little improving. When you first open the app you will be asked to log in, which is a bit of a hassle, but you can set it to remember you so you can bypass that. However, if you love Skype like I do, you are going to be disappointed with the chat option. Instead of showing you the different chats, it shows you the chats by individual person, which means you can only chat with one person at a time. Nimbuzz also logs you out after 30 mins, unlike Fring which kept you logged in forever.

Last words: Nimbuzz is a great app and with a few more tweaks especially around convenience, it will be perfect.

SkypeThe Skype brand itself doesn’t need much of an introduction, however the Skype mobile app does. Skype currently supports two versions: full and lite. The full version was launched in early 2009 after a breathtaking wait. It’s easy to install and can be download via SMS or through the web. Its interface is quite simple and intuitive and given that it’s a facsimile of the desktop app, the learning curve is not that steep. Most users know what to expect and where/how to find things.

The full version, as the name indicates, offers users all the options available on the desktop client such s chatting, calling, sharing files, etc, with friends on your for free. if you have a Skype paid account, then you can call cell phones and landlines locally and internationally at the same Skype rates.

The full version, however, doesn’t support the video option and is only supported on iPhone and Windows Mobile.

The lite version is supported for most other platforms, including Android, and it’s not really a mobile VoIP application, since it doesn’t work over Wi-Fi and 3G. Calls made using the lite version count towards your plan minutes, but you can reach your Skype contacts (for a fee).

The lack of video support on the mobile app is less than ideal. However for an iPhone user, who is not looking to connect with other social communities, Skype full version offers most of the features you could want.

Last words: I would like to see Skype do more innovation in the mobile space. Given its reputation, it should be able to offer extremely powerful features to its users around multi-OS support and voice quality (I have found Skype’s quality of voice better using Fring and Nimbuzz than the Skype app itself). Having said all of that, Skype’s mobile app continues to be one of the most popular products on the iPhone App Store, and although other apps are currently better than Skype, I have a feeling that will change in 2010.

truphoneTruphone is getting a lot of traction in the UK and the Europe/Middle East/Africa market. It touts its service as a comprehensive communications offering on users’ mobile devices. Truphone started as a simple VoIP client for Nokia Symbian S60 devices but has quickly transformed into a unified client that does it all. Like Nimbuzz and Fring, it lets you integrate with other communities such as Skype, Google Talk, MSN and Yahoo and supports Twitter (only on your iPhone and iTouch). Calls and SMS texts to other online Truphone users are free, and calls or texts to other numbers are chargeable unless you have a Skype in/out credit account.

Truphone supports full Skype functionality on iPhones, iPods and Android, which means you can make (and receive) Skype calls and send instant messages to other Skype users for free. It supports both Wi-Fi and the 3G cellular network.

Unlike Nimbuzz and Fring, Truphone competes with Skype by offering a telephony service, which includes unlimited calling to 38 countries (landlines) and cell phones for 9 countries (including US, Canada and China).

Based on my experience, Truphone has done a decent job with its interface but still needs to iron out a few kinks. One place where Truphone easily wins is in its better call quality, but it is still more expensive than Skype, and that is one of the reasons, if I had to use the Truphone app, I would only use my Skype account on it.

To its credit, Truphone won an award from the British Interactive Media Association (BIMA) for best Mobile App/Game.

VoriumVopium is an another app, which is causing a stir in the mobile VoIP market. It’s free to download to your mobile phone from and primarily tries to save you money by redirecting your international calls through the cheapest possible routing.

Vopium claims to be compatible with more than 500 handsets across Java, Symbian, BlackBerry RIM, and Windows Mobile. However, I’ve only tested it on my iPhone and Android device and found it generally easy to download and install. Users can use the Vopium app to make and receive free calls around the world to and from other Vopium users using Wi-Fi and the 3G Network. That’s pretty standard with the other mobile VoIP apps listed above.

Vopium users keep their own mobile number and SIM card and maintain their numeric identity when making calls, which is a cool feature. Vopium doesn’t support any interactions with other communities such as MSN, Google or Skype, etc, like its counterparts listed above. It has recently added an Android client to its growing portfolio of applications, and it’s now available on Android Market.

Vopium offers a JustDial feature, which is less of a mobile app offer, but it lets you use any telephone that doesn’t have Vopium software installed to call a number and it will use its own service to offer you a cheaper rate than the telcos. So if you were in, say, India and had access to a landline and you wanted to call a US mobile number, you could go to Vopium’s site and enter the Indian line number and the US mobile number on the Call Back page. Instead of a costly fee for directly dialing the number while roaming, you’d only be charged for calling an Indian landline and a US mobile, resulting in greater savings.

However, the rates that Skype offers for a use case as above are still 50% more discounted than Vopium’s offering, so there’s no big win there at least for my case. But overall, after using Vopium’s service on my iPhone, I’ve found the quality of voice is much better than Skype’s, so it does get “mobile” points there.

Overall, I have found Fring to be the mobile app that best suits my needs, is easiest to use and gives me access to much more than just a VoIP utility, but since there’s no one size fits all, other people might find other traits and apps more useful.

But one thing is for sure, mobile VoIP is going to be even bigger next year. Imagine you are on a Virgin America Flight from San Francisco to New York and you have free Wi-Fi on board but no cellular network, what would you do if you wanted to make a call to your friend?

Don’t miss MobileBeat 2010, VentureBeat’s conference on the future of mobile. The theme: “The year of the superphone and who will profit.” Now expanded to two days, MobileBeat 2010 will take place on July 12-13 at The Palace Hotel in San Francisco. Early-bird pricing is available until May 15. For complete conference details, or to apply for the MobileBeat Startup Competition, click here.

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