Circuit Builder is described as 'This App is designed to be an introduction to constructing and operating electronic circuits. Intuitive controls and layout make Circuit Builder the perfect App for understanding the basics of electrical and electronic circuits' and is a circuit simulator in the education & reference category. There are seven alternatives to Circuit Builder for a variety of platforms, including Android, Windows, Linux, Web-based and Mac apps. The best Circuit Builder alternative is Circuit JS, which is both free and Open Source. Other great apps like Circuit Builder are CircuitJS1 Desktop Mod, Everycircuit, VoltSim and Experimenters Circuits.