iCircuit is a user-friendly electronic circuit simulator and editor billed as ideal for students, hobbyists and engineers. Its advanced simulation engine can handle both analogue and digital circuits and features real-time, always-on analysis.
You use it as you would any CAD program: you add components, connect them together, and configure their properties. But iCircuit is unlike other CAD programs because the simulation is always running. It’s just like working with the real circuit. Instead of stopping to make a measurement or spending a lot of time compiling reports, you simply play with the circuit and see what happens. [via]
Circuit design/simulator app runs on iPhone, iPad and MacOS - [Link]