iCircuit is described as 'Its advanced simulation engine can handle both analog and digital circuits and features realtime always-on analysis. It is the perfect companion to students, hobbyists, and engineers' and is a Circuit Simulator in the Education & Reference category. There are more than 25 alternatives to iCircuit for a variety of platforms, including Windows, Mac, Linux, Online / Web-based and Android. Most alternatives are Circuit Simulators and Electronic Design Automation Tools. The best alternative is KiCad, which is both free and Open Source. Other great apps like iCircuit are Circuit JS (Free, Open Source), Fritzing (Paid, Open Source), QUCS (Free, Open Source) and LibrePCB (Free, Open Source).
PCBWeb is a 100% free Windows desktop CAD application for designing and manufacturing electronics hardware. Features include schematic capture, PCB Layout with gerber output, and Bill of Materials manager.
Physical things are great. Hardware companies like Apple, Arduino, etc are disrupting our lives in a big way. At BrainBox we love hardware hackers and are in absolute awe of their awesome design and applications they build.