While newer, headline-grabbing rival WhatsApp is sticking (for now) with its "no ads" policy, Microsoft is busy persuading marketers that they can reach the so-called Millennial generation by advertising on Skype.

The internet telephony and instant messaging platform, owned by Microsoft since 2011, says the number of 18- to 24-year-olds using the service is rising 28 per cent year-on-year. Although Skype has fewer global users than Whatsapp (300 million versus 450 million), it argues that its audience is more engaged.

The tech giant is highlighting the fact that its service tends to be used for “sustained” connections with close family and friends that “demand deep attention”, thereby creating an “intimate environment” for advertisers to exploit, it claims.

The Millennial demographic, forever “bouncing between apps on their smartphones, PCs, phones and tablets”, is pausing to have relatively long conversations on Skype, Microsoft says, with users putting in an average of 30 minutes per call and 150 minutes a month on the platform.

Skype recorded 862,000 unique users in Ireland last January, according to comScore figures. “Skype is big in Ireland and it is still growing,” says Christian Jago-Byrne, Microsoft Ireland’s digital advertising manager.

"Brands definitely want to be better connected with consumers across their media journey," adds Jago-Byrne, who manages advertising products across the MSN portal, Xbox, Outlook.com and Windows Phone, as well as selling advertisements on the Skype home page and instant messaging chat window.

One youth-targeting company that has taken advantage of Microsoft's multi-screen platforms in the Irish market is Lucozade Energy, which has advertised across Skype, Xbox, MSN and mobile as part of the high-profile "powered by glucose" campaign planned by the agency Mediacom.

In larger markets than Ireland, Microsoft offers a Windows 8 product called Ads in Apps, through which it sells advertising for both its own Skype, Xbox and Bing apps and third-party apps including Shazam and AccuWeather.

“Every year seems to be ‘the year of mobile’, but I think it’s really beginning to take hold,” says Jago-Byrne.

The advertising industry is still playing catch-up with consumers, however, and he cites format difficulties posed by screen size as one reason for the lag. “But we are starting to see some real innovation in the Irish market . . . Brands and agencies are very progressive in what they are doing.”