This DaringFireball post made me think a little bit about the recurring (2015, 2014, 2013, 2012) theme of "Apple is too dependent on a single product".
There's no doubt that Apple's results and future are closely tied to the iPhone's continued success. But I also think it is important to think about how much that concentration on iPhone has created the success.
Gruber's comment about Apple's rapid and enormous growth (i.e., both its rate as well as its rate in the face of its large size) highlighted, again, the importance of having a small suite of products (the fabled: "We can put all of our products on the table you're sitting at"). It's not news that the sharp focus allows Apple to break the mold of low-return device sales. My small question of the day is whether, beyond customer satisfaction, the only way to manage a giant company (at least by market cap) successfully is to have a narrow portfolio of products? I'm distinguishing between a complex company and a complicated product mix. There can be a lot of activity (a complex company) that supports the sale of those products but, to make sure efforts are coordinated, the products (and thus goals) must be few.
And the portfolio is even smaller than it may appear. The criticisms of "iPad is a just a big iPhone" and insight that AppleTV is just a display-less iPhone also mean that the products have significant overlap. Which means that the supporting underlying activity for each is largely complementary.
And, as I write this, I realize it may be captured in the Asymco post I just linked to - from 2010 (of course Asymco figured this out a long time ago). Oil companies (the title is "Apple vs. Exxon-Mobil") are another example of giant complicated companies with small portfolios.