Startup Idea: Mobile CAD Design App Start-Up Idea

Startup idea to develop a mobile app, enabling users to design CAD-like programs on their tablets or smartphones. The app should ideally support free-hand drawing with a stylus and touch screen, and should be compatible with existing CAD or Sketchup projects. This app aims to provide reliable CAD solution for users on the go.

I would like to have a program or app that would allow me to design CAD-like programs possibly using free-hand drawing with a stylus, or a touch screen. Perhaps something that can be used on a tablet or a phone. Integrated compatibility with CAD or Sketchup projects would be preffered.

Essentially, a CAD program I could use on the go. I have. I have searched "CAD apps for Android" but I haven't found a reliable one yet.