Gentry Underwood: Why was there this strange gap in the market that we were able to move into? The gap was created by mobile devices themselves. It’s very natural when a new platform comes along to expect behavior to work as it did in the old platform, which means, for a smartphone, take a desktop email client and jam it down into the mobile device, because that’s all you know. You don’t know how people’s behavior is going to be different; you’ve never seen it before. Well, turns out we use our mobile phones really differently than we use our laptops. It’s taken us a while to figure that out and understand it, and that creates a design opportunity for a different kind of tool. Fundamentally, Mailbox is not an email client so much as it in an inbox, oriented around delightful processing.