More recently, Skype has lagged behind its competitors.

In April the company said Teams had amassed 75 million daily active users. But even at Microsoft, it's not the star. Skype did get a boost from the virus. In March Microsoft said that Skype had 40 million daily active users, up 70 percent from the previous month.

Skype is still around - it's just been upstaged. The absence of Skype in the implementation exemplifies the video-calling service's diminishing presence in a year when competitors became more prominent than ever, as the coronavirus pandemic forced people to connect online. LinkedIn employees worked with the team behind Microsoft Teams to build the integration, Szeto said. LinkedIn employees use Blue Jeans internally, and they also chose to incorporate 'the other most popular services, Zoom and, in our own backyard, Teams,' Chris Szeto, senior director of product, told CNBC. The effort stemmed from a project engineers developed for a Covid-response hackathon LinkedIn held earlier this year.

Online skype calling