The number of its users is growing by the population of Singapore (more than four million) every 12 days and nearly a third of its registered subscribers now use it for business purposes.

As if to celebrate its fifth birthday, IP telephony service provider Skype recently achieved a milestone of 15 million concurrent users, meaning there are now 405 million skype users across the planet. This figure, they say, is growing by 380,000 every day.

Skype, an eBay company, unveiled these extraordinary figures in Singapore, to mark the launch of its new software Skype 4.0, which it describes as 'the most exciting and fundamental change to Skype's software in the company's history'.

Despite the downturn, Skype last year earned US$550 million in revenue, a 44 per cent rise, year on year. In the final quarter 2008, they earned US$45 million -- the eight consecutive quarter of profit.

The company offers free calling between subscribers and low-cost 'Skype Out'calling to standard landline telephones and mobiles. The software, also allows calls, file transfers, texting, video chat and videoconferencing. The service is available for desktop computers, notebook and tablet computers and other mobile devices, including mobile phones. A number of companies, including Skype, produce dedicated Skype phones.

'Skype Out' revenue growth

According to the company, in the fourth quarter of 2008, people used 2.6 billion 'SkypeOut minutes' and that is growing by 61 per cent quarterly.

According to preliminary data, released by TeleGeography Research, Skype accounted for eight per cent of the world's international calling minutes in 2008.

Skype maintains that separate research points to 95 per cent of business users saving money using it, with about a third cutting their phone bills by half. Almost 80 per cent of the survey of 'Skype for Business' users, showed that nearly 80 per cent had seen an increase in productivity and were working closer with their co-workers because of using Skype.

Perhaps most telling of all, the research shows that some 62 per cent of business subscribers were using Skype to better communicate with their customers.

Keen to grow its business subscribers, Skype now even offers a free 'Business Control Panel', a web-based tool that allows company's to control all of their Skype credit expenditure.

Super wideband audio

Skype 4.0, which took three years to develop, is claimed to be 'more user-friendly than ever before' to offer higher quality audio, through 'super wideband audio' and a new bandwidth manager that provides 'the very best Skype video calling experience possible, even on a low bandwidth connection'.

According to Dan Neary, Skype's new Vice President and General Manager, Asia Pacific, "there has never been a better time than now for enterprises -- particularly small to medium businesses -- to consider switching to Skype for their communications".

"In this type of environment people are looking for cost savings wherever they can find them, they are looking to 'recession-proof' their businesses," Neary said. "They don't want to fly from A to B, they want to do video-conferencing. More and more, this offering is becoming applicable for people in business.

"We are quite happy to offer many services that are free, because we know that some people are always going to want to upgrade to our premium paid services."

Other 'paid for' Skype features include on line numbers, Skype Voicemail and Skype SMS.

This story, "Skype Growing by 380,000 Users a Day" was originally published by CIO .