Tim Cook was asked the first question (on the iPhone portfolio). His answer is paraphrased here:
We haven’t so far. That doesn’t shut off the future. Why? It takes a lot of really hard work to do a phone right when you manage the hardware and software and services in it. We’ve chosen to put our energy on doing that right. We haven’t been focused on working multiple lines.
Think about the evolution of the iPod over time. The shuffle didn’t have the same functionality as other products. It was a really good product, but it played a different role — it was great for some customers it was strikingly different than other iPods. The mini played a different role than the classic did. If you remember when we brought out the mini people said we’d never sell any. It was too expensive and had too little storage. The mini proved that people want something lighter, thinner, smaller. My only point is that these products all served a different person, a different type, a different need. For the phone that is the question. Are we now at a point that we need to do that?
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At a macro level, a large screen today comes with a lot of tradeoffs. When you look at the size, but they also look at things like do the photos show the proper color? The white balance, the reflectivity, battery life. The longevity of the display. There are a bunch of things that are very important. What our customers want is for us to weigh those and come out with a decision. At this point we think the Retina display is the best. In a hypothetical world where those tradeoffs didn’t exist, you could see a bigger screen as a differentiator.
Full interview here, answer begins around minute 37.
Here is how I interpret the answer:
