But now, with the advancement of technology, many new types of software are getting introduced to the world. The default video player of Mac OS is QuickTime Player, which was the most popular one for Mac users. These two questions confused many people on the Apple community and Quora. 'How do I change the default video player from Quicktime to VLC?' 'How do you change the default media player for Mac OS X?' 4.15 10 Easy Way Do Split-Screen on Mac.