https://www.theverge.com/2018/9/28/17913174/microsoft-office-universal-apps-windows-10-development

Microsoft first started work on its touch-friendly Office apps for Windows 8.1 more than five years ago. Designed for tablets or laptops with touchscreens, the apps are lightweight and speedy versions of Word, Excel, and PowerPoint. Microsoft has updated them regularly for Windows 10, but now that the company has halted work on Windows 10 Mobile, it’s also halting work on these Office apps.

The apps aren’t fully dead yet, but Microsoft is no longer developing new features for them. “We are currently prioritizing development for the iOS and Android versions of our apps; and on Windows, we are prioritizing Win32 and web versions of our apps,” explains a Microsoft spokesperson in a statement to The Verge.