The PLC Simulator App by DavidRWhite is an excellent tool for beginners who want to learn how a PLC works and experiment with simple programming. The app consists of three main sections: "How a PLC Works," "PLC Block Diagram," and the PLC Simulator. With 3 timers, 2 counters, 6 compare instructions, 2 binary outputs, and 3 RES outputs, the PLC Simulator allows beginners to learn simple programming skills.

The user interface is very user-friendly, and there is an information icon for first-time users to make programming easier. The app also helps users to understand the exam-off instruction -[/]-, the "Seal-In" or "Latching" logic, such as a motor start/stop circuit, and much more. My daughter found it very useful for her Mechatronics class, and I highly recommend it to anyone who wants to understand the basics of PLCs.