Searching apps for Lofi Prototying

I’m looking for tools that can help creating low-fidelity, prototypes (that a client absolutely cannot mix up with a design composition and start discussion stylistics) for apps and websites. I’m fine with either a web, mac or an iPad app. Also I’m open to it either create a hand-drawn style programmatically or straight up make use of the Apple Pencil, but provide some methods above only painting (i.e. detecting shapes and creating reusable components.