If you want a glimpse of how we'll interact with computers in the future, watch Justin Kan use his iPhone. Then you'll see how Kan was able to: 1. source a playlist of southern hip-hop; 2. change his Virgin America ticket to an earlier flight; 3. book a helicopter taxi to make the new flight; 4. buy a rare Ducati motorcycle, and 5. haggle over its price—using a single, simple smartphone app.

You'll notice this wonder-app has a green icon, and that it's already on your phone. Kan was texting the whole time.

Specifically, he was testing the limits of Magic, a new-ish service that promises to get users whatever they want, "on demand with no hassle," simply by texting a human concierge. Kan's requests, documented in a recent blog post, presumably are more extravagant than anything you might do. He's the multimillionaire co-founder of live video platforms Twitch and Justin.TV, so buying a Ducati through a stranger via text message is no big deal. Still, there's relevance to the rest of us. The SMS shopping spree is a variation on a theme that's generating a considerable amount of attention among designers and developers. It illustrates the exciting new possibilities of humble old chat.

Justin Kan

You might trace the spasm of chat enthusiasm to China. Last December, in a blog post on Chinese app trends, designer and engineer Dan Grover announced the emergence of "chat as a universal UI." Grover had moved from San Francisco to Guangzhou to work as a product manager for popular messaging app WeChat and noted the advent of "official accounts" for brands and public figures on the service. "Think SmarterChild but for banks, phone companies, blogs, hospitals, malls, and government agencies," he explained, likening the accounts to the friendly AIM bot of yore. Today's WeChat users ask their bank about their balance much like you and I once pestered SmarterChild for movie times.

WeChat official accounts don't merely let users "connect" with a company or service in the same sense that Twitter lets users "connect" with Velveeta. The accounts provide utility that the rest of the smartphone-using world tends to compartmentalize into apps. As Benedict Evans, mobile guru at a16z, has noted, a WeChat user can "send money, order a cab, book a restaurant or track and manage an ecommerce order, all within one social app." Though sometimes WeChat might mean interacting with a human employee, other times a bot, and still other times with a shortcut on-screen, those interactions constitute a model of mobile interaction fundamentally different from our own. It's a model in which chat is the do-everything portal for mobile life. In this way, you can see WeChat and Magic as distant relatives. Both put conversation ahead of apps as the primary means of getting things done.

WeChat and Magic are distant relatives. Both put conversation ahead of apps as the primary means of getting stuff done.

Why would anyone want to interact with their bank through text? For one reason: Texting is easy. It's familiar. According to a recent study by Pew Research Center, text messaging is the most widely used smartphone feature, accessed by roughly 97 percent of users. As Jonathan Libov noted in his own blog post on messaging-based interfaces: "In contrast to a GUI [graphical user interface] that defines rules for each interaction—rules which, frustratingly, change from app to app—text-based, conversational interactions are liberating in their familiarity." Texting is an interactional medium in which we're already fluent.

Libov stresses just how comfortable chat has become as a means of communication. Consider how we make plans with friends: We text back and forth, even when a phone call would be faster. Or think about the latest advent in the world of customer service: the live chat session. It's perfectly suited for simple queries that otherwise would have to find their way through the impregnable automated phone menu. If you've ever been late getting out the door to an Uber, you might've encountered the universal utility of chat there, too. Even though the app sends an automatic notification upon your ride's arrival, when drivers really want you to know they're waiting, they go rogue and send a text. What's more, we're already starting to see some services take up messaging as their main channel for interaction. Digit, a startup that encourages people to save money, communicates with users via SMS.

Texting is easy. It's familiar. We're at home in our messaging apps.

Text messaging as it exists now could be an efficient, lightweight way to get basic information, but if a smartphone maker like Apple were to get behind the idea of chat as an interface, it could make messaging vastly more capable. Matt Galligan, co-founder of the recently closed news aggregation app Circa, explored this idea in a recent blog post. He imagined an Apple-built "MessageKit" that would let developers atomize functionality and repackage it for conversational consumption. Services like Lyft and and AirBnb would live in iMessage as well as on your home screen. Galligan used OpenTable as an example. You'd type "Can I get a table for two at Namu Gaji tonight?" to the OpenTable contact in your message app, and that'd be it, Galligan writes. "Isn’t that so much easier than jumping through all of the hoops of navigating an app?"

Matt Galligan

Something like MessageKit would require a serious shift in our collective outlook on smartphone software. It would be an unequivocal signal from Apple that we were entering post-app territory, a move that undoubtedly would spook developers. But there's reason to think some might find life inside iMessage attractive. Today, companies fight bitterly to get their apps installed. What if people could summon services via text instead? Say I'm talking to a friend about getting lunch. What if I could invoke a Yelp bot for a recommendation that would appear right there in the chat, even if the other person didn't have the Yelp app installed. I can't imagine Yelp would mind. In this future, conversations could become an organic, social vector for "app" growth.

It may always feel silly to talk out loud to Apple's virtual assistant; maybe Apple should let us text Siri instead.

Even if we never see anything quite as radical as MessageKit, there's suggestion that mobile software is heading in this direction. The new iOS 9 search will try to pull relevant information out of apps and place it directly in search results. If rich bits of live application data can end up in search, why can't they end up in text messages? Plus, what's Siri if not a very expensive bet that someday we'll warm up to a conversational user interface? It may always feel silly to talk out loud to Apple's virtual assistant; maybe Apple should let us text Siri instead. It's also worth mentioning Slack. The popular workplace app, in many ways a souped-up messaging app, is itself emerging as a fertile ground for experimentation with message-based bots.

Chat-based user interfaces pose all sorts of meaty design challenges. One is visibility. When features exist not as buttons on-screen but simply as paths a conversation might take, how do you make sure people understand all the possibilities available to them? A service like Magic is only magic because there's a resourceful human being on the other side of the exchange. Remove the human, and things get considerably tougher. As Matt Webb, co-founder of the defunct design studio Berg put the challenge in a thought-provoking post on conversational interfaces, "How does a user have a theory of mind about a bot—a conception of its stance, intentions, domain of knowledge, etc." The real potential of chat-based UI won't be unlocked by giving everyone a real live concierge. It will require encouragement from smartphone makers, buy-in from third-party apps and services, and a good dose of thoughtfully tuned automation.

Still, the simple versatility of text messaging is a very attractive quality. And the value of its familiarity can't be overstated. Every breakthrough computer interface has been easier to use than its predecessor. The command line was replaced by the graphical user interface and point-and-click mouse. Smartphones and touchscreens distilled those into swipes and taps. There aren't many things easier than downloading an app and tapping a few virtual buttons with your finger, but sending a text message might be one of them.