Not so long ago, Skype was the only serious contender for calling friends, family and colleagues over the net. Yet a few years, and an unpopular major update later, Skype has gone down in the estimation of many Mac users. At the same time, Apple released its answer to Skype - Facetime - which is rapidly climbing the download charts as a serious alternative. It's therefore about time we put Skype and Facetime head-to-head to see which is the king of calling.

Interface

Until the update to version 5, most Mac users were satisfied with the interface of Skype. Since the latest version however, many have found the new large-screen interface intrusive, unintuitive and basically harder to use than previous versions. Some have even gone back to the much slimmer version 2.8. Facetime meanwhile has a very simple interface which instantly detects your iSight camera on startup and makes calling contacts simple. Even better, it automatically detects contacts in your Address Book so you don't have to mess about adding them. However, it is still very basic compared to Skype at this stage of its development.

Result: Facetime draws with Skype 5 on interface at this stage of development.

Flexibility

Skype can be used on both Mac and Windows and you can call landlines or mobiles anywhere in the world. In terms of flexibility and interoperability between platforms Skype takes some beating. Facetime however is very much locked into everything Apple. Its not even available on Windows, works only on Macs or iPads, you can't call landlines and the only mobiles you can call are iPhones.

Result: In terms of flexibility, Skype wins hands down.

Cost

Skype is free to download. Facetime costs $0.99 to download on the Mac App Store (although rumor is that it will be bundled free in new Macs sold with forthcoming Lion OS X) and there is no trial version. Both allow free calls between computers (Macs only in the case of Facetime) and mobiles with either Skype or Facetime installed. However, Facetime allows group video calls for free. Skype have now made this a Premium feature in version 5 costing $4.99 a day or $8.99  a month. Overall, it depends on your needs.

Result: If it's just calls to one person, then Skype wins by virtue of the fact you have to pay to download Facetime. However, Facetime offers the best value for money if you're going to be group calling regularly, even if you are more limited in who you can call.

Updates

Both allow auto-updating from within the apps. However, as many Skype users have already done so on Mac, you can easily roll-back to version 2.8 if you're unhappy with version 5.0 by simply downloading and reinstalling it. Not so with Facetime. As with all apps from the Mac App Store, there's no rolling them back if you're unhappy with the new look or features.

Result: Skype gives you more power and choice when it comes to accepting new updates.

Call Quality

This is a hard one to judge because much will depend on the quality of your internet connection. In terms of audio, both are about the same. In terms of video however, on a 1-Mbps connection Facetime offers incredibly high quality HD video chats of 720p. Unfortunately though, HD quality is limited to new MacBook Pros due to the iSight camera requirements. Every other MacBook user has to do with VGA quality which is still pretty good. Skype also offers HD calls but both you and the person you're talking to need Skype 4.2 for Windows or higher plus HD webcams. For everyone else, Skype video calls are in the same 640x480 VGA resolution as Facetime. Both Facetime and Skype support full-screen video too.

Result: Depending on your connection speed, call quality is a draw.

Conclusion

The app you prefer will depend on what you need it for. Overall, while Facetime is very promising, Skype still remains the superior calling tool because of its flexibility. Facetime can only be used with other Mac and iOS devices and that will be a major drawback for many users. Skype allows you to call anyone, anywhere and that remains its over riding appeal.

Overall Result: Skype wins until Facetime becomes more open and flexible