A Few Questions about Facebook's new ad policy

Here is a link to Facebook's announcement about their new ad policy and how users can "opt out".
https://www.facebook.com/help/585318558251813

Here are the questions I have:
1. Is "Digital Advertising Alliance opt out" the same as what's also known as "Do Not Track"?
Here is the link http://www.aboutads.info/choices/
2. Does Facebook's new policy only apply to mobile devices? I did not see anywhere that "desktop" was specifically mentioned and only a mobile device is shown in the video.
3. When Facebook says in its info about using web history and apps, does this mean Facebook will somehow get all the info it can from any mobile app installed to share with ad companies?
4. Does "app" also mean Facebook will try to get info from desktop apps (or only mobile)?

 

1: No. The former is done by opt-out cookies. The latter is a signal that is sent to websites via HTTP header.

 

When you see references to "web," I believe they mean any web browser on any platform. When they use the term "app," I believe they mean mobile apps only.

 

More info here.