Explanation:

Box 1: No
Box 2: Yes
Box 3: Yes
When you create an app, or someone shares an app with you, you can run that app on Windows, iOS, Android, or in a web browser.
References:
https://docs.microsoft.com/en-us/powerapps/maker/canvas-apps/app-from-sharepoint
https://docs.microsoft.com/en-us/powerapps/user/run-app-client