One of the more eagerly awaited new features in Windows Phone 8.1 is the ability to project the handset to display to a secondary screen via wireless Miracast or wired USB technologies. This feature works much like screen projection in Windows 8.1, and is useful for those that need to show their Windows Phone handset to others in real time.
Note: Thanks to Microsoft's Cliff Simpkins for providing some valuable info for getting this to work.
Years ago, I had hoped to use something like this to create Windows Phone training videos. At the time, Microsoft used special Windows Phone builds to project their handset screens during demonstrations and industry events, but I was never able to secure the necessary hardware and software. However, with Windows Phone 8.1 picking up so many new features from mainstream Windows versions, this is no longer an issue. Now anyone can project their Windows Phone screen.
Depending on your handset hardware, you can choose between Miracast-based wireless screen projection and USB-based wired screen projection. Each requires a bit of additional software or hardware on the other side, so to speak. For example, to use wireless screen projection, you will need a Miracast-equipped display, still rare, or a display hooked up to a Miracast device. For USB, all you need is a normal USB cable, but the PC needs to be running Microsoft's Project My Screen application.
Since my Nokia Lumia 1020 doesn't support Miracast, I chose USB-based projection. Here's how it works.
First, install the desktop application noted above.
Then, connect your Windows Phone handset to the PC via USB. On the device, sign in and navigate to Settings, Project My Screen.
If all goes well, Windows Phone will quickly prompt you to allow the connection.
If not, Mr. Simpkins offers some good advice for fixing the problem: Open Device Manager and remove the phone from Portable Devices and all entries for the phone in Universal Serial Bus devices. If you're prompted to reboot, don't do so. When you're done, just unplug and replug the phone and it should work.
The Project My Screen desktop application runs full screen by default, and this is how many will want to use it. But you can press ESC at any time to view it in a resizable window. Be sure to check out "Advanced" options on the phone, too: You can enable such things as a touch circle, indicating where you're touching the screen, and different orientations.