With internet giant Google reportedly testing out a VoIP service within Gmail, this could spell trouble for Skype. But there are other services available if you want to make web-based calls, and they've got plenty of ammo to give Skype a run for its money. Here is our pick of the bunch:
Initial reports from Cnet suggest that voice calls from within Gmail would be separate from the existing Google Voice, which provides you with a voicemail service along with an access number that calls all of your phones.
Although Google already offers voice and video chat, it seems that the new service puts the emphasis on making phone calls. It appears that calls to US and Canadian numbers (from within North America) would be free, as would internet-only calls. Skype currently charges 2.1c per minute for the same service on a PAYG basis. If it goes ahead, then it represents yet another string to Google's increasingly heavy bow.
Details are thin on the ground, but we'll keep you updated as soon as we hear anything new.
Although focused on VoIP, Vonage tries to cover all the bases by also covering home, business and mobile phone calls to any mobile or landline in the world. As it isn't PC-dependent, you really only need a broadband connection. The comprehensive range of services makes it a strong competitor, not only to VoIP firms, but also to landline service providers.
Vonage's mobile app taps into your Facebook contacts, effectively enabling you to call them for free, providing that your data plan is up to the job. Available for iPhone and Android, the app offers calls over Wi-Fi or 3G and can be used internationally, although obviously that could result in some fairly hefty roaming data charges.
By offering as many services across as many platforms as possible, Vonage has all its bases well and truly covered, offering a one-stop shop for all your voice calling needs.
A mobile-phone based system using either Wi-Fi or 3G, Fring offers free video calls, voice calls and live chat to other "Fringsters" as the firm, somewhat optimistically, hopes you'll refer to them as, along with friends on other social networks.
You can call your friends on MSN Messenger, Google Talk, ICQ, Yahoo! and AIM friends for free, while Fring can also be used to make cheap local and international calls to landlines and mobiles. Until recently, the service also supported Skype, but it seems that the latter has blocked Fring from carrying out video calls within its network. The service is compatible with all smartphones, says the company, and is available over any mobile internet connection including 3G/4G, Wi-Fi, GPRS and EDGE. What's more, Fring supports almost every mobile OS you can think of including Symbian S60, iPhone/iPod touch, Android, and Linux.
Despite the lack of Skype support, Fring does offer access to a lot of the major IM clients, as well as the all-important 3G functionality.
Designed specifically for use on mobile phones, Truphone offers free Wi-Fi calls to other Truphone, Skype or Google Talk users. You can also make cheap international calls to landlines and mobiles from any Wi-Fi hotspot in the world by routing calls through the Internet, in order to avoid expensive roaming charges.
Truphone is compatible with Apple, Android, Nokia and Blackberry devices and despite the lack of 3G support, this is a great VoIP service for people that make a lot of international calls. Providing, of course, that they can find some Wi-Fi.
Compatible with both Mac and PC, Nimbuzz offers free voice calls and enables you to instant message your chums across the most popular IM and social networking services. You can also make cheap international calls to landlines and mobiles around the world.
The Nimbuzz mobile app lets you chat with friends on the go, supporting an impressive number of IM clients. It also offers VoIP calls and lets you share photos, videos and files. It's available on pretty much all of the big mobile OSes including iPhone, Android and Symbian.
With support for most of the big IM platforms and cheap international calls, Nimbuzz offers the best of both worlds.
Which VoIP service do you use? Are there any others out there that could rival Skype? Let us know in the comments box below.