Once you find out how to do it, it’s great! – Digital Circuit Simulator Lite Review

This is as good as doing it on a computer! It has flip flops and all gates. I haven’t built anything yet in it so I will see about lag. Also I’m not for sure if you can create a intergrated circuit. But it’s really good for it being free! Scrolling with a circuit/gate is a bit too fast.
Review by Max5923 on Digital Circuit Simulator Lite.