Windows 10 and Windows 10 Mobile users may get a new feature that will allow them to keep working on the same document or app even if they switch devices. This feature will reportedly be similar to the Handoff fuction for Apple's OS X and iOS.
According to Winbeta, this feature will allow a user on a Windows 10 PC to write a Word document, stop in the middle, and then continue on their Windows 10 Mobile phone, and vice-versa:
If the user is unaware they can do this, Cortana will helpfully inform you that you can resume working on a document or email once you're away from your desk, making it far easier to access your workflow. This feature should work in more than just productivity apps too; For example, when using the Maps app, you can look up directions on your PC before leaving the house, and then pull up the Maps app on your phone once out and about and resume exactly where you left off on your PC.
There's no word on when this update might be released, but Microsoft could mention it as part of their Build 2016 developer conference announcements on March 30.