Ipad integration is a great option for creating CAD models when sitting at a computer is not an option. Support for the stylus/pencil is pretty intuitive.

The application is quite intuitive and you can easily do complex shapes without much work.

The user experience is SO thoughtful. It contextually changes what options are available, and has some sort of memory so if you were just looking at an arc, it will actually be more likely to connect a new line to the path of that arc. The iPad use is fantastic which is how I primarily use it, but using it on my Mac is great too. I use it every few days to design whatever I want.