I knew a lot about product design before coming to Apple, but I didn't understand a lot about consumer experience design, which is really Apple's forte.

It wasn't until the Apple Macintosh that people understood what true hardware-software integration was about. It took one company to line it up: low-cost hardware, cool graphics, third-party products built on top of it, in an all-in-one attractive package that was accessible to consumer marketing.

You need to set near-term milestones. Put the assumptions down on paper, and make it to your vision or ultimate product. Your team has to understand where they're going. Your partners need to understand where they're going.

It can't be that difficult to build a great thermostat. So I decided to figure out: What would the thermostat for the iPhone generation look like? I got this bug. It really infected my brain. I kept thinking about it. This could be a cool product that matters and a cool product that has a great business.

Typical mergers happen when there are two competitors coming together, and they reduce overhead.

You start with the right amount of rational and emotional experiences. You have to blend those in your product when you come out.