A great resource:

https://creator.oculus.com/getting-started/immersive-media-glossary/

Play the videos from local storage for the best rendering. Either transfer files from a computer of download them.

Data in the header of the file that contains information about the video like the projection. If no metadata is included, the user will have to select the format in the player at runtime (2D, 3D Side by Side, 3D Top Bottom, etc...).

The player looks better than other third party apps