No one ever accused Mark Zuckerberg of standing pat.

The Facebook social network has expanded to over 1.2 billion people across the globe, and the company has successfully moved its primary application — "the big blue app" — onto smartphones. Skeptics may wonder if Facebook can keep all those users. But Zuckerberg doesn't concede that’s even an issue. Instead, he's figuring out how to plug his social network into all the other apps that run on your phone. He’s thinking ahead, plotting his transition to a new world of computing, one that includes rapid-fire messages, wearable devices, and maybe even virtual reality.

>In the past, Facebook encouraged coders to build right on top of its social network. But now it must find other ways of connecting with the rest of the internet.

Today, at its F8 conference in San Francisco, the company is reaching out to software developers, hoping to enlist their help in this push toward the future. When Facebook ran mainly on our desktop machines, inside our web browsers, Mark Zuckerberg and company encouraged coders to build right on top of their social network. But now, in a world of standalone smartphone apps, they must find other ways of connecting with the rest of the internet. Yes, Facebook has bought popular apps, like Instagram, and it's building new ones through its Creative Lab. But Facebook also sees itself as a resource for the entire community of app developers, providing all sorts of tools that help developers build, run, improve, and monetize their apps — even if their contact with Facebook is glancing.

Zuckerberg divides this developer mission into three themes. First, the company is revamping the Facebook Login process – which allows people using third-party apps to use Facebook information like friends – giving users more control of personal data. Second, he vows that Facebook will become a more stable platform so that outside developers can build stuff that plugs into the social network and be confident that work done will not have to be altered. And, third, the company is augmenting a suite of tools that lets other outfits create all sorts of apps that run cross-platform, i.e., on iOS, Android, and Windows.

But as the company woos developers in San Francisco, so much else is afoot. Facebook is buying powerhouse products like WhatsApp (a bargain at $19 billion?) and, more recently, the fitness app Moves. Looming in the future is the impact of Facebook’s purchase of the Oculus VR technology, which Zuckerberg sees as the next big advance in computing. Meeting with me on Facebook’s Menlo Park, California campus and later via phone, Zuckerberg explained his developer philosophy, his belief that all apps should be social, and his vision of Facebook as the leader in knowledge — which as he described it, sounded a lot like search.

WIRED: At previous F8 developer conferences, you have launched big products for your consumers, but this time, you’re focusing on developer tools. Why?

ZUCKERBERG: This is really about our platform growing up. Most companies that have major platforms have big events for their communities that are separate from when they’ve launched big products, and in the past, we used F8 to launch big new products or big directional changes in the platform. Now, we want to get the community together once a year around the same time to review all of the different offerings that we have to help people build, grow, and monetize their apps – and, for us, to go over everything that we’ve been doing and get feedback. We’ll have separate events and separate times when we make big changes or launch big new products, but that’s not what F8 is gonna be about going forward. It’s really about having this grown-up stable platform.

>While originally a Facebook developer was someone who wrote an app to run actually on Facebook, now you’re building infrastructure for developers to do cross-platform mobile apps.

WIRED: Over the years, the nature of a Facebook developer has evolved, hasn't it?

ZUCKERBERG: It certainly evolves with the technology platforms that we use of the day. Right now, mobile is becoming increasingly important, and that's what we’re seeing: most of those developers now are using Facebook platforms to build apps. So, while originally a Facebook developer was someone who wrote an app to run actually on Facebook, now you’re building infrastructure for developers to do cross-platform mobile apps.

It was only really for the very first year, or 18 months, that most of our platform was about building apps inside the website. At the time, even though it’s a little hard to remember, we only had 24, 25 million people actively using our product. Thinking about a product that was so small at the time as the identity and social layer for the whole web, or all of the apps that people use, would’ve been silly. So we started with people building inside Facebook, but within a year or two, we were on our way to 100 million people and beyond, so we quickly rotated toward trying to be a layer where you can log into websites or apps to bring your social contacts with you.

It’s hugely successful — more than 85 of the top 100 apps use Facebook. A huge number of them use Facebook to get app installs, and we’re becoming critical infrastructure for people to build their apps with all these different cross-platform services, like identity sharing, push notifications, app installs, and monetization.

WIRED: You’re announcing changes to Facebook Login that let users resist requests for too much information. That’s less about helping developing than it is protecting users from developers.

ZUCKERBERG: Our philosophy is that we care about people first. In the case of login, some of the things that we’re doing may add a little bit of friction to the experience by giving people the opportunity to not share certain things with apps. That will mean that developers will have to adjust. Over time, making it so that people trust the blue button to log in to Facebook will ultimately be good for developers, too.

A screenshot of Facebook Login's new anonymous login tool. Image: Facebook

WIRED: It seems you’re also responding to the idea that people in general are uneasy about how much information is on Facebook, and sharing that information with developers might give them pause.

ZUCKERBERG: When we were a smaller company, Facebook login was widely adopted, and the growth rate for it has been quite quick. But in order to get to the next level and become more ubiquitous, it needs to be trusted even more. We're a bigger company now and people have more questions. We need to give people more control over their information so that everyone feels comfortable using these products.

WIRED: Also, you’re now allowing people to use Facebook Login without revealing who they are.

ZUCKERBERG: Yeah. But I don’t think that this is making anonymity on Facebook. What it’s doing is allowing someone to sign into an app without revealing who they are to the app. But then we also offer this nice upgrade path so that after you’ve signed in anonymously, if you are comfortable telling the app your information, you can easily do that. You can maintain a seamless experience without having to set up a new identity within the app because it's all continuous.

WIRED: Another theme of F8 is stability. Facebook will have scheduled upgrades over time and even adopt version numbers for the platform like we see in operating systems. Doesn’t this run counter to the Facebook ethic of ship first and ask questions later?

ZUCKERBERG: We’ve changed our internal motto from "Move fast and break things" to "Move fast with stable infrastructure."

WIRED: It doesn’t have the same ring to it.

ZUCKERBERG: It doesn’t, which I think is partially why it hasn’t caught on externally. But by building a stable infrastructure, we allow ourselves to always make sure that we’re moving forward, even if we move a little bit slower upfront. Because when you build something that you don’t have to fix it 10 times, you can move forward on top of what you’ve built. We’re applying that same philosophy now to the development community. The API that developers use is actually the same as we use to deliver our own mobile apps. The vast majority of the platform usage is our own, so it needs to be super stable. We’re also going to commit to a two-year stability guarantee for our core APIs. These are real changes that we’re making so people can rely on us as a critical infrastructure for building all of their apps across every mobile platform.

>We’ve changed our internal motto from 'Move fast and break things' to 'Move fast with stable infrastructure.'

WIRED: Is this the beginning of Facebook’s middle age?

ZUCKERBERG: I don't think so. You have to be stable in order to get to the next level. All the best platforms are.

WIRED: The previous F8 was all about apps running on what you call the Open Graph. We don’t hear much about that these days. Did that work?

ZUCKERBERG: Open Graph is a language for structuring content and sharing that goes on in other apps, and we’re continuing to build it out longer term. But we found we need to build more specific experiences around categories like music or movies. Where we’ve taken the time to build those specific experiences, stuff has gone quite well. Some of our launch partners like Spotify and Netflix have made a lot of progress. In some other areas, like news, we’ve gone in a different direction and focused on our own public content and newsfeed ecosystem. But we’re continuing to invest in Open Graph, and I'm still quite excited about it long term.

WIRED: Another one of the big categories you promised with Open Graph was fitness apps. Instead of having a developer step up in that category, you bought a company called Moves. Will you run that independently as you do with Instagram and say you’ll do with WhatsApp?

ZUCKERBERG: Yeah, although those guys are going to join us in developing some of our other products. They've done some really great work with location, and we’re really excited about building more location-sharing tools as well. We just announced Nearby Friends, which is the start of a really interesting type of utility for people. We’re really excited to explore that area more.

WIRED: How should we look at this growing family of apps you’re building – as part of the Facebook family, or apps that just happen to be owned by Facebook? Will you run them all from one big backend, like one kitchen that serves multiple restaurants that might look different to the diner?

ZUCKERBERG: Over time, they’ll integrate in different ways, but right now, we’re more focused on making them each excellent at the things that they do. This fits in with the overall platform strategy. We’ve always believed that there were going be a lot of different ways to share content, and that we were never going to build all of them ourselves. We try to build the most important ones. But on top of that, you’re going to see dozens of other apps that developers build that each use the Facebook login, Facebook to share, the mobile "like" button, push notification from Parse, app installs through Facebook, and Facebook monetization tools in order to turn their apps into businesses. It's going to be one great community where people will have the ability to share whatever content they want with whoever they want.

WIRED: Do you think every app should be a Facebook app?

ZUCKERBERG: I don’t know. There always needs to be a balance of things. People have recently asked me what I think about trends like not using real identity. When Facebook was getting started, nothing used real identity – everything was anonymous or pseudonymous – and I thought that real identity should play a bigger part than it did. But I don't think it will get to a point where everything uses real identity, because there’s always gonna be a place for different services using different kinds of social interactions. Over time, I think we might do more of these things as well. So whereas you only think about Facebook as real identity today, you’re going to see us do different things. Instagram and WhatsApp aren’t based on your name as a real identifier. They’re based on a pseudonym identifier. So when you ask if everything should be a Facebook app, I really think the question should be: "Should every app have social components?" The answer to that will probably be yes.

>Whereas you only think about Facebook as real identity today, you’re going to see us do different things. Instagram and Whats App aren’t based on your name as a real identifier.

WIRED: Since Facebook is almost synonymous with social apps, I’ll take that as a yes to the original question.

ZUCKERBERG: There’s another way to look at it. One of the big themes for F8 is building cross-platform apps. Right now, you have these different mobile silos – iOS and Android and Windows. But when someone buys a phone, they don’t want to be limited to just the apps and experiences on that phone. Developers don't want to be trapped in any given silo, either. So if you're asking should every app be social, I think partly you’re asking whether every app should have components that work across these silos, like identity or sharing or push notifications or app install distributions. Those are basic things people want and developers want. So yeah, every app should be social and have tools that go across platforms. No one’s building those today, so that’s what we’re going to focus on.

WIRED: You recently clarified your mission of Facebook into three things: connect everyone, understanding the world, and building the knowledge economy. I’m intrigued by the second part: What does it mean to have Facebook understand the world?

ZUCKERBERG: We’ve been talking about apps and experiences for helping people share and communicate. But over a five-year period, people will start thinking about social networks not just as communication tools, but also knowledge tools. There's all this knowledge being shared, whether in private messages or in Facebook posts on Facebook or structured data through Open Graph, and right now, there isn’t a great way for us to try to surface that to you, either from a search perspective or a discovery perspective. We have a big focus in our company on trying to help make all that knowledge useful to people.

It turns out that between 5 and 10 percent of posts on Facebook are people asking questions to their friends, everything from "Where should I go on this trip?" to "Who should be a drummer for my band?" Those are questions that you wouldn’t ask a traditional search engine. The knowledge probably exists within our system to provide some insight for you. If we can do that, it’ll change how people think about social networks from being just about communication to being about knowledge and answering useful questions. So we’re doing a bunch of things, whether it’s Graph Search or Open Graph or different discovery tools or the Nearby Friends feature we just launched. The app platform plays into this too, because that’s about getting a lot of knowledge and content into the ecosystem that we’re not working on ourselves.

WIRED: You launched Graph Search a year ago but it’s been a slow adoption.

ZUCKERBERG: Graph Search is still really early. We haven’t even rolled it out on mobile yet, and that’s where most people use our products. We don’t call it a beta because I don’t know if we call anything a beta, but it is really a work in progress. There’s still a lot of content that we haven’t structured yet, so it will be a few more years before we really get through everything. It’s a huge effort, right, where the corpus of information that we’re indexing is bigger than any web search engine that you would find out there. We just have to do it step by step. As we do it, we’re trying to make it useful, but this is a multi-year thing.

>When you put on the headset and you try it out, you really do feel like you’re there within seconds. Then you realize that the system that’s delivering this experience is using commodity hardware with cell phone screens.

WIRED: Finally, one question about the Oculus purchase. You’ve said that the acquisition was driven by your belief that some years from now virtual reality could be a dominant computing platform. What made the light bulb go off in your head to trigger that belief?

ZUCKERBERG: I think using it is the biggest thing.

WIRED: What made you feel that – just like you were saying a couple years ago that Facebook should be "mobile first" – the company should eventually be "virtually reality first"?

ZUCKERBERG: When you put on the headset and you try it out, you really do feel like you’re there within seconds. Then you realize that the system that’s delivering this experience is using commodity hardware with cellphone screens, and can be manufactured for a low number of hundreds of dollars, and this can be in a lot of people’s hands. It’s something that people talked about for a long time, but I think now the economics and performance are finally there where this could work.

When you think about what it takes to build a mainstream computing platform, communication is probably the most important use case and we bring a lot of experience to that. Gaming is where VR will initially take off. We’ve done a lot of work there, and the Oculus team is extremely strong. I felt like if we combined those efforts, we could build something really special.

Correction 13:35 EST 05/01/14: An earlier version of this story referred to Facebook's third-party-site login service as Facebook Connect. It is now called Facebook Login.