With the explosive growth of smartphones, tablets, and super-sleek laptops, mobile usage continues to grow as a percentage of overall Internet usage. In some countries, moreover, smartphones have already vaulted past laptops and desktops to become the dominant personal-computing device. In these countries, companies should obviously focus on mobile first.

But in the developed world, which already has a massive installed base of desktops and laptops, bigger screens are still extremely important. And they are likely to remain so, even when everyone who uses them also owns a smartphone and tablet.

Cory Bergman responds:

[N]ews organizations should shift to a mobile-first approach immediately. This doesn’t mean we ignore the desktop, but prioritize mobile over it — make mobile the default everything. When brainstorming a new product, start with a phone or tablet design and work backwards to the desktop. Set performance goals based on mobile performance over desktop.