Office on Android
The biggest change to Office over the past year was the introduction of apps for Android phones and iPhones. (The iOS version will install on an iPad, but Android tablet users are out of luck.)
You won't find any live collaboration features, such as the ability to view live typing or to chat with editors, on these apps. Nevertheless, I found the Android app worked well for making quick edits, viewing comments, or monitoring document additions while on the go. If mobile chat is something you absolutely need, there's always the Skype and Lync mobile apps, but switching between Office and Skype/Lync on a smartphone can quickly become a hassle.
Tracked changes are a glaring omission from Office mobile. You also won't be able to differentiate between each editor's contributions on a collaborative document the way you can on the desktop or Web app.
The assumption with Office Online is that the apps are deliberately hobbled so they don't undermine the company's desktop business. That may be true, but Microsoft has the fundamentals covered with its Web apps and has slowly been incorporating new features.
Last summer, Excel Online added the ability to create freeze panes, and Word now auto-saves your document. So if you need basic spreadsheet or word processing functionality or want to see live typing as you collaborate in real-time, Office Online will work for you. Once you need to do something particularly advanced, however, like creating PivotTables or sparklines in Excel, you'll need the desktop apps.
More so than any other version of Office, Office 2013 and the new Office 365 service try to try to make collaborating with colleagues a simple, seamless experience. It's moved closer to that goal thanks to gradual improvements to the Web apps and the addition of mobile versions of Office for Android and iOS. Unfortunately, features like chatting and live editing are often unwieldy. Until Microsoft can work out these and other idiosyncrasies, it will be hard to take Office seriously as a collaboration contender.
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