PhET Interactive Simulations vs TableTop Science

PhET Interactive Simulations provides interactive science and mathematics simulations for students from preschool through university. Its design emphasizes scientific inquiry, visual mental models, multiple representations, real-world connections, and flexible classroom use; the simulations include virtual experiments and guided lessons. PhET says simulations are evaluated for educational effectiveness through student interviews and classroom observation. All are open source, and they are written in HTML5, with some legacy simulations in Java or Flash. They can run online or be downloaded. Android and iOS apps include HTML5 simulations and translations for offline use and automatically download new HTML5 simulations. A desktop app provides HTML5 and Java simulations and translations for offline use on Windows and macOS. The service is available on the web, Windows, macOS, iOS, Android, and select Chromebooks. Android browser-based HTML5 simulations and Linux are not officially supported. The free simulations plan is available to students and teachers. Commercial use requires a license from the University of Colorado Boulder.

TableTop Science has no write-up on Specifiction yet; its figures are above.