Mobile Apps, Card Interfaces, And Our Opposable Thumbs

Editor’s Note: Semil Shah works on product for Swell, is a TechCrunch columnist, and an investor. He blogs at Haywire, and you can follow him on Twitter at @semil.

This is a post about “cards” as an interface in mobile apps. I am not a designer. I am also unable to mention every single app that uses cards — feel free to mention others in the comments. Additionally, I don’t know which apps should be credited with popularizing cards, or when that happened. For this post, it doesn’t matter. I’m also going to be talking about cards in the context of iOS, because that’s what I know, though it applies to any mobile device.

With those disclaimers out of the way, I want to share why I believe “cards” are becoming more prevalent as a mobile interface. As I was tweeting about cards over the last few weeks, a friend pointed me to a great blog post by noted mobile expert Luke Wroblewski, in which he demonstrates his design thinking in designing the app Polar in an age when mobile users look at their phones hundreds of times per day, often for only a few minutes at a time. Wroblewski’s post is worth reading and includes a short, insightful video on users’ “finger behavior.”

The essence of all of this boils down to the following, which we all intuitively understand: We use our phones most often with one hand, and more specifically, we navigate with one finger — the thumb. It’s all in the thumb, says Wroblewski, and I would bet scores of other designers agree. This may be why we see navigation buttons on the bottom of apps (Instagram), or anticipatory cards that push relevant information to users (Google Now), or drawers or “hamburger” icons to reveal settings or menus (Facebook), or radial buttons that open up a series of possible actions (Path), or advanced left-to-right swiping gestures in email apps (Mailbox), or why photo-sharing network apps use the “flick up and down” gestures to scroll through images (Frontback). The list goes on and on.

All of this thumb-swiping makes me wonder: Should nearly every mobile app be rethought of in this “thumb-dominant” context? Surely some apps require more digits for interaction, and some require that users type more (maybe both thumbs, or some eccentric combination), but beyond those, if the thumb is essentially the mouse for touch-enabled mobile devices, the “card” on a mobile device becomes more and more important as a digestible unit of information on a small screen for users who are on the go and mostly glancing through their apps before settling into the ones that truly engage them.

I have been thinking about cards because the company I work for (Swell) uses them. As an audio/news player, the app uses a cards interface to let users swipe left-to-right to skip tracks, to swipe upward to bookmark, and to swipe down to reveal advanced controls. This isn’t to say every app should use cards, of course, but users do seem to like the simplicity of the dimensions and seem to intuitively understand the physics of turning a card over for more information and controls. And, well before mobile devices, cards were always all around us — business cards, playing cards, and so forth. In fact, one of the reasons I got interested in this concept, not being a designer, of course, is the memory of baseball cards, that most everything I needed to know about a player could be contained on both sides of a small playing card.

A two-sided card seems to fit nicely in this mobile age. Perhaps that’s why Tinder’s user interface is so popular as its users quickly flick through picture tiles, or why Apple’s Passbook and Reminders apps use a cards interface with information and controls on both sides, or why a NYC-based entrepreneur named Jordan Cooper is trying to rebuild mobile web pages into cards as the focus of his new startup, Wildcard.

Going back to some of the pre-iPhone iPods, even back then we could scroll through album art. Perhaps that was the beginning of cards. Perhaps we’ve been trained to swipe cards on mobile devices for over a decade now, and that interaction appears to be here to stay. Whatever the origin, it may be moot — the snacking, on-the-go, one-handed behaviors of mobile users today seem to indicate that, for now, a one-thumb navigable card is the interface of choice, and until the next designer invents that new atomic unit and corresponding gestures to go along with it, we will have to sit tight and keep shuffling the deck.

Photo Credit: Sarah Reid / Creative Commons Flickr