iCircuit is the easiest way to design and experiment with circuits. 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.

You use it as you would any CAD program: you add elements, connect them together, and set their properties. But iCircuit is unlike other CAD programs because it is always simulating. It's just like working with the real circuit. You do not stop to take a measurement or spend a lot of time configuring reports. Instead, you just play with the circuit as you normally would, with the power on!

There are over 30 elements you can use to build your circuits. The app has everything from simple resistors, to switches, to MOSFETS, to digital gates.

The app features a multimeter that you use to probe around the circuit to instantly read voltages and currents. If you want to see how a value changes over time, then you can add values to the built-in oscilloscope. The scope can simultaneously track many signals over time and features a variety of automatic modes that make it easy for you to grasp the behavior of your circuit.

You can even export your circuits and PNGs, PDFs, and SVG files so that they are easy to include in reports or web sites. Scope data can even be exported for offline analysis.

See a tutorial videos at:

Supported elements include:

• Signal generators, Voltage sources, and Current sources
• Resistors, Capacitors, Inductors, Potentiometers, Regulators
• SPST/SPDT Switches, Relays, and Transformers
• Diodes, BJ Transistors, and MOSFETs
• Speakers, Microphones, Buzzers, DC Motors, and LEDs
• Op-amps, ADCs, and DACs
• Logic gates: AND, OR, NAND, NOR, XOR
• JK and D Flip-flops
• Over 30 74XX series ICs

What’s New

Version 1.9.1

Arduino support for:
* Serial.println
* Floating point numbers
* Syntax coloring in the editor

Ratings and Reviews

3.9 out of 5
48 Ratings

48 Ratings

Fyngyrz ,

Good basic teaching / learning tool

Mostly keyboard driven; needs contextual menus for basic component rename and so forth. Delete key does nothing; only backspace works, where delete is the obvious key to… delete… something. Needs a “test point” component. Needs (a lot) more digital components, there are only 18. No adders, no ALUs, no selectors like 3-to-8’s, etc. The more, the merrier, eh? Needs a little bit more lively simulation of things like lamps; they should light, I think, and buzzers should buzz, speakers should speak, etc. Be nice if an overloaded component smoked, too. 1/4 watt resistor with 5w power dissipation? Sizzle… ! :) But you don’t get to set the wattage of the component, so… this is a significant issue in terms of realism. One thing in particular that would be *lovely* is if you could drag values; for instance, say you want to DC bias a BJT NPN transistor’s collector 1/2 way between vcc and ground. Okay, so set the hFE as desired, put a resistor from the base to vcc, set a couple limits like 1k and 500k, now drag a slider and watch the scope. bingo, ultra-convenient bias setting. That kind of thing would make this into a deisgn tool, even if a very simple one. It would also be educational.

Overall, this is really fun, and I’m really comfortable using it to teach the basics. But it could be a great deal more, and I hope that at some point, it is. Well worth the price.

odra94 ,

Missing some things

I really like this app. I am using it for my classes to simulate circuits. It is simple, easy to use.

However, it is missing some things. There are no XNOR gates and also the Text Label tool does not work for me. It does not let me edit the text inside it. It just goes vertically in the box and I can’t edit it. It might be just a bug. Otherwise I really like it.

ampguru ,

Unreliable for real applications

Pros: No Ads!

Cons: It doesn’t work!

This app is very unstable and only works sometimes. Every time I make a change to the circuit the emulator doesn’t give a response (i.e. observed voltage change when a resistor value is changed). I have to save the file close and reopen to see the response I was looking for. Sometimes, I just get a convergence error and the circuit doesn’t work, but it worked previously. Now its not even letting me save my circuit, prompting me to write this frusturated review. A good concept, but you cant rely on this app to give you accurate results. Don’t waste your money.


Krueger Systems, Inc.
5.1 MB

OS X 10.7 or later, 64-bit processor



Age Rating


  • Family Sharing

    With Family Sharing set up, up to six family members can use this app.

More By This Developer