The No. 3 Apple iOS E-Mail Program Is Microsoft's Outlook

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  • Nine-month old app has almost 30 million users monthly
  • Product is helping lure more customers to Office 365

Microsoft Corp.’s mobile Outlook app has gone from zero to three in nine months flat.

Since acquiring Acompli Inc. for $200 million last December, Microsoft has become the No. 3 ranked e-mail software for Apple Inc.’s mobile operating system. The company has amassed almost 30 million unique monthly users for the products it has rechristened Outlook for iOS and Android. Not bad considering Acompli arrived with just “hundreds of thousands of users” said Javier Soltero, the Microsoft Outlook vice president who was Acompli’s co-founder and chief executive officer.

That rate of usage means Microsoft’s e-mail app on iOS is just ranked behind Google’s Gmail and Yahoo Mail, Microsoft said, citing the third-party measurement service App Annie. Winning over more of these users is important for Microsoft’s efforts to stake a claim in mobile as it scales back making its own phones. Having compelling e-mail software available on the iPhones that many workers use is helping persuade companies to sign up for Microsoft’s Office 365 cloud apps, Soltero said.

Microsoft is releasing Wednesday a new version of Outlook for iOS with an update for Android scheduled for November (and one for Windows some time this year). The new version adds some of the calendar features from one of Microsoft’s other iOS and Android app purchases, Sunrise. As Microsoft continues to combine the two, “eventually Sunrise will be sunsetted,” Soltero said.

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