Primary difference between PPTX & KEY is, PPTX is a Microsoft PowerPoint file format that’s can use on both of Apple iOS & Windows PC, and KEY is an Apple Keynote file format that’s only can use on a Apple iOS.
PPTX
This is a Microsoft PowerPoint Document. PowerPoint has both version of Apple OS & Windows PC, so you can create or edit a PPTX file by Mac OS computer & Windows compatible computer. We use PowerPoint 2016 version to create Freepiker template & we recommend you for use that same or updated version to get all animation, transition & proper effects.
KEY
This is an Apple Keynote Document. Apple Keynote is only for Apple OS, So you can create or edit a KEY file by Mac OS computer (iMac, Macbook, MacPro, iPad, iPhone etc.). We use Keynote 7.1.1 version to create Freepiker template & we recommend you for use that same or updated version to get all animation, transition & proper effects.
NOTE: Please remember that what you are looking for before download.