VoIP applications

Voice over IP, or VoIP, is an emerging technology that allows you to use your broadband Internet connection to place and receive voice and videophone calls. Internet-based calls are less expensive than traditional calls (sometimes they’re even free), and many VoIP-based communication services are compatible with the old-fashioned global phone network, so you can use these new VoIP tools to place calls to and receive them from traditional phone numbers. By adding some desktop VoIP software tools to your Mac, you, too, can take advantage of Internet calling.

We’ve reviewed four Mac-compatible desktop VoIP applications: Apple’s iChat AV 3.1.4, SIPPhone’s Gizmo Project 1.3.2, SightSpeed 4.5, and Skype 1.4. We also checked out a unique product called WengoPhone; still in beta for the Mac, this VoIP plug-in for Mozilla Firefox lets you make and receive calls via the browser.

While each program has strengths and weaknesses, they all do basically the same thing: they present you with a buddy list like the one in an instant-messaging (IM) program, and they allow you to communicate by voice (and sometimes video) with the folks in that list. Perhaps the best thing about these VoIP apps is that they’re free downloads and aren’t shareware, so they won’t time out or periodically nag you to register. Since these programs are free, their makers do charge for some premium features.

To get started using VoIP, you’ll need a broadband Internet connection (cable or DSL) and a Mac running OS X 10.3 or 10.4 (some of these tools—iChat AV and Skype, for instance—offer additional functions to Tiger users). You’ll also need a microphone and a pair of speakers or headphones. Serious desktop VoIP users will opt for headphones or even a headset-microphone to eliminate echo, one of the negative side effects of using freestanding speakers.

Cross-platform connections

Some VoIP products, including Skype and Gizmo Project, run on Windows and Linux, while Apple’s iChat AV runs only on OS X.

Skype, SightSpeed, Gizmo Project, and iChat AV allow you to host either multiparty voice or videoconference calls. Unlike expensive high-end conferencing systems designed for large businesses, which are often connected to a telephone system, these simple desktop VoIP apps can make conferencing easier—and more affordable. All of these applications allow you to call other Internet users for free. But if you want to call somebody using his or her telephone number, as permitted by Skype, Gizmo Project, and the Wengo plug-in, you’ll pay a basic, per-minute fee. At this writing, neither iChat AV nor SightSpeed permits computer-to-phone calling.

Advanced features cost money

While you can make basic calls for free, more-advanced features will cost you. For instance, Skype’s voice-mail feature carries a small monthly charge. Obtaining a permanent phone number from Skype (called a SkypeIn number) involves an additional fee. Also for a fee, Gizmo Project allows you to forward your incoming calls to another telephone, such as your cell phone, and SightSpeed offers extended conferencing and video-messaging features for paid subscribers. iChat AV users can’t call traditional phone numbers, but they can call each other, using securely encrypted audio channels on the Internet if all participants are .Mac subscribers.

Once you become accustomed to a desktop VoIP tool, you may find that VoIP calling becomes a part of your daily routine. After all, it’s a lot easier to dial a Skype buddy by double-clicking on a name than it is to look up a number in Address Book and manually punch it in on your telephone’s keypad. If you’re into multiplayer Internet games, using a tool like Skype to keep in touch with your teammates is nice, as it relieves you from having to type text-chat messages during the game. And if you have relatives in other countries, talking to them over the Internet will cost you a lot less than placing international long-distance calls.

Some downsides

Despite the benefits of VoIP software on the Mac, a traditional phone is still necessary in some situations. Chief among them is emergency calling. None of the apps we looked at can properly route a 911 call to your local emergency dispatcher, though they’ll probably have this ability in the future. Some services that require entering digits—such as telephone banking or certain corporate phone menus—may not work properly with the computer-to-phone features of Skype and Gizmo Project, due to differences in the way VoIPsupports dialed touch tones.

Discovering which VoIP app is right for you involves a combination of research, experimentation, and (hopefully) a little fun.