Semi-Touch Versus Multi-Touch
Lexus Navigation has what I'd call a semi-touch interface. That's one where some of the interaction happens on the touch screen and some happens with buttons or controls off the touch screen. Semi-touch isn't bad or good. It just means that you have some fixed interface elements. When you design one of these types of systems you want to make things people do all the time easy to get to. You also want those things quickly accessible to avoid having the driver get distracted. In the Lexus design they also want to be able to completely or partially disable functionality while still giving you a button to press that makes you feel like you're doing something. The Lexus Navigation system has eight button-like objects around the screen. Design-wise that's probably good because the buttons aren't too big or too small. Seven of the buttons are functional. One of the buttons isn't really a button even though it looks like it. It's labeled "Passenger.&
