This app is an electronic circuit simulator that runs in the browser.
This app lets you simulate the behavior of arbitrary electrical circuits. You can add volt meters and ammeters to your circuit to see where currents are flowing.

It’s an excellent tool for both students and electronic enthusiasts. Its design is based on colors that can indicate for example positive or negative voltage, and allows you to build simple circuits with mouse clicks.

You can design, analyse and test a circuit virtually in a browser.
This app simulates the behavior of an electronic device/circuit, it is cheaper, quicker and often more practical to simulate a circuit than to physically build one. 
Supports Chrome, Firefox, Safari, Edge, IE11+