Microsoft Teams gained 12 million users in just one week following a surge of remote working to combat the spread of the COVID-19 virus.
The communications platform reported 44 million users as of 18 March, up from 32 million on 11 March.
The figures came as the conferencing service celebrated its third birthday, but also just a few days after it suffered a two-hour outage - likely linked to the sudden influx of users.
Microsoft's corporate VP for 365, Jared Spataro, said that the service had seen an "unprecedented" spike in usage in just seven days. He also suggested that the numbers might not drop when the coronavirus pandemic is under control.
"It's very clear that enabling remote work is more important than ever, and that it will continue to have lasting value beyond the COVID-19 outbreak," Jared Spataro, Microsoft's corporate VP for 365 wrote in a blog post. "We are committed to building the tools that help organisations, teams, and individuals stay productive and connected even when they need to work apart."
For its third birthday, Microsoft added some new features to Teams. The first is a function that uses AI to reduce background noise - which will certainly be welcome following the government's decision to close all schools. There is also a button allows users to read messages while offline and a 'raise hand' feature to help get their questions across during busy video meetings.
Although Teams is now far ahead of the competition, a leaked Microsoft partner video suggested the company is keen to thwart rival video conferencing service Zoom. An alleged internal company video, posted to Twitter on Thursday, suggests Microsoft sees Zoom as an 'emerging threat' to Teams as it is often used by businesses in tandem with Google's G Suite and fierce rival Slack.
This week, Slack also unveiled a host of new functions and reported a spike in users due to the coronavirus. The smaller platform saw over 7,000 new users in just 47 days, according to TechCrunch. For context, it only recorded 5,000 new users in its last quarter report.
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Bobby Hellard is ITPro's Reviews Editor and has worked on CloudPro and ChannelPro since 2018. In his time at ITPro, Bobby has covered stories for all the major technology companies, such as Apple, Microsoft, Amazon and Facebook, and regularly attends industry-leading events such as AWS Re:Invent and Google Cloud Next.
Bobby mainly covers hardware reviews, but you will also recognise him as the face of many of our video reviews of laptops and smartphones.