Many of these learning tools are written in Adobe Flash and published in .swf format.
From a computer:
You may need to download a Flash Player from Adobe’s website which allows you to run .swf files.
From a mobile device:
Mobile browsers do not support the Flash Player. In order to access Flash content, you need to download a Flash Browser from the App Store or Play store. While there are many options, the free Puffin Academy App has whitelisted mathies, ePractice and MathCLIPS.
Hints for using Puffin Academy.