"Using real-time co-authoring, colleagues, friends and family can contribute and edit documents simultaneously in the Word Web App, PowerPoint Web App or Excel Web App," Microsoft said in a blog post.
If someone is making a change to a document, the other person can see it happening on their screen. Like Google Drive, real-time editing in Office Web apps will display the names of those who are actively editing a document, all of whom will be assigned a specific color.
Microsoft Web Apps went live in 2010 - five years after Writely.com, the first online word processor, hit the Web—and four years after Google absorbed Writely into Google Drive, then known as Google Docs. It was a Web-based version of Microsoft Office 2010 with Word, Excel, PowerPoint, and OneNote, and was billed as a "companion" to desktop-based Office.
Redmond previewed an update to Web Apps earlier this year, announcing plans to extend Web apps to Android in addition to iPads and Windows 8. It tipped co-authoring at the time, rolling it out first to the PowerPoint Web app.
"We're still on track to enable editing from Android tablets, so you can access Office files and tools from even more devices," Microsoft said today.
For now, Microsoft has rolled out updates to Word, PowerPoint, and Excel.
In Word, Microsoft said it has improved formatting controls. "New features include ability to find and replace words and phrases, apply styles and formatting to tables, and insert headers and footers for more professional reports and papers," the company said.
For Excel, Microsoft added the ability to drag and drop cells and reorder sheets. "The Excel Web App will give you a quick analysis of a range of data right in the status bar, including sum, count, and average of a selected range of cells," Redmond said. "And we now support more workbook types online, you can now open and interact with spreadsheets that have Sheet Protection."
Finally, on PowerPoint, there is new picture cropping functionality and the ability to change the name of your files within the editing window of PowerPoint Web App, and across the other Office Web Apps.
For more, check out PCMag's original review of Office Web Apps.