What Does Platform Agnostic Mean?

Platform agnostic is a a concept that refers to the design attributes and philosophies of software products. A platform agnostic product runs equally well across more than one platform.

Techopedia Explains Platform Agnostic

If the platform agnostic term is used, the platform must be defined. When referring to a software product, platforms typically refer to common operating systems (OS), like MS Windows, Mac OS, and Linux.