It's weird, I find myself using Facebook less each year. Looks like I'm in the minority:

Nine out of ten of the 1.55 billion people a month who use Facebook access it on a mobile device at least part of the time, and more than three-quarters of its $4.3 billion in advertising revenue in the third quarter of 2015 came from mobile users. The company runs four of the six largest social platforms in the world (all but Google’s YouTube and Tencent’s WeChat) and is wildly profitable. Three years ago, when the company revealed that 1 billion people logged in to the service in one month, the news was astounding. Last August, 1 billion people used Facebook on a single Monday, and it felt inevitable.

How Facebook made Instagram even better:

Zuckerberg, unlike many of his rivals, has been able to keep his leadership team stable. Their cohesiveness led to the second key moment: the Instagram acquisition and its subsequent success.

When Facebook announced that it was buying the photo-sharing juggernaut in April 2012, less than six weeks before its IPO, a flurry of articles followed with titles such as "Five Ways Facebook Will Ruin In­stagram." Instead, the deal became a model for how businesses in Facebook’s portfolio get managed. Zuckerberg left cofounders Kevin Systrom and Mike Krieger in charge, encouraged them to preserve their own culture, and gave them access to tools—from Facebook’s recruiting team to its spam-fighting technologies—that helped them get where they were planning to go anyway, only faster.

"Schrep and I work day-to-day, operationally, on how we build our team, where we hire from, organizational stuff," says Systrom, Instagram’s lanky, bearded CEO. "Mark and I work most closely on product. And Sheryl and I work most closely on advertising and strategic issues around policy. Imagine getting to have Mark, Sheryl, and Schrep on your board. Many companies in the Valley would kill to have that. And we get it by default, which is pretty sweet." Instagram’s user base tripled in the 10 months after the acquisition announcement, to 100 million monthly users, then doubled in the next 13 months. (It now boasts 400 million users.)

Next up for Facebook: Virtual Reality and Artificial Intelligence. 

If you’ve ever felt like your Facebook News Feed is filled with people you don’t care about sharing thoughts you didn’t particularly want to hear, you’ll appreciate why Facebook is pushing to further the art of artificial intelligence. In its current form, the social network is still far better at collecting vast amounts of data than understanding what that data means. Advanced AI could help emphasize the stuff that’s truly relevant to you, keeping you on the service longer and boosting your attractiveness as a subject for targeted advertising. "Facebook is working to be at the center of the world of AI because it will affect Instagram, WhatsApp, and Messenger," says Systrom. "It’s broadly applicable to all social products."

Facebook has dabbled in AI for years. In 2010, for example, it introduced facial-recognition technology to identify people in photos. In late 2013, though, Zuckerberg came to believe that AI—which he calls "one of the hardest engineering challenges of our time"—was central to the company’s future and decided to establish a lab devoted to it. He began courting Yann LeCun, a New York University faculty member and world-class expert in deep learning, to run it. Unlike the archetypal young turk Facebook employee, the 55-year-old, Paris-born LeCun is an éminence grise of his craft, with decades of experience studying machine vision, pattern recognition, and other technologies with the potential to make the social network smarter.

LeCun, however, was disinclined to leave academia or New York. When Zuckerberg thinks Facebook needs something, though, he refuses to treat obstacles as obstacles. He offered to let LeCun set up Facebook AI Research’s headquarters in Manhattan and retain his professorship on the side. LeCun came aboard. Problem solved.

Because Zuckerberg would not be able to interact with LeCun in person on a daily basis, he had the AI researchers who did work at Facebook’s main campus sit near him so he could learn from them. "When we moved to the new building, we ended up being separated from Zuck by about 10 yards," LeCun chuckles. "He said, ‘No, this is too far, move closer.’ " And so they did. (This is a signature move that Zuckerberg uses to absorb new material; when the team prepared Facebook’s Timeline feature in 2011, he placed key design talent near his desk, and he seated Systrom near him after the Instagram acquisition.)

The mandate for the 50-person AI team is also vintage Zuckerberg: Aim ridiculously high, and focus on where you want to go over the long term. "One of our goals for the next five to 10 years," Zuckerberg tells me, "is to basically get better than human level at all of the primary human senses: vision, hearing, language, general cognition. Taste and smell, we’re not that worried about," he deadpans. "For now."

In part, the AI effort is an attempt to prepare Facebook for an era in which devices from wristwatches to cars will be connected, and the density of incoming information which the service will have to deal with will grow exponentially. "There's just going to be a lot more data generated about what's happening in the world, and the conventional models and systems that we have today won't scale," says Jay Parikh, the company's VP of engineering. "If there's 10x or 20x or 50x more things happening around you in the world, then you're going to need these really, really intelligent systems like what Yann and his team are building."

On Internet.org:

But it can’t do anything for people who remain disconnected from the digital world. "If we really want to connect everyone in the world and give everyone the ability to have a voice and share what they want with the people around them, then you can’t just build the biggest Internet service," Zuckerberg says. "You also have to help grow the Internet." In 2013, Facebook enlisted Nokia, Qualcomm, Samsung, and other tech giants to help it found Internet.org, the global-connectivity initiative dedicated to bringing the Internet to the 60% of people worldwide who aren’t yet online.

The effort is a hybrid of short-term altruism and long-term capitalism. "The fundamental connectivity problem is a financial one," Sandberg explains. "For 90% of the people, it’s cost. The World Bank puts absolute poverty at about $1.25 a day. One in six people live under that. If you’re the average connected Facebook user in the U.S., you spend a dollar a day implicitly on data. So the business models have to change, and the cost needs to go down. And that’s what we’re trying to do."

"It’s not lost on our businesses that as economic standings improve, there will be opportunities, but that’s not the initial goal," adds Matt Grob, CTO of Qualcomm. "We’ve seen throughout the world that when you provide improved connectivity, people are more able to educate their children and participate in political and government activities and sell their wares or find jobs."

Internet.org’s first effort—an app offering free access to Facebook, news, search, job listings, and other services—is live in India, Indonesia, Pakistan, the Philippines, South Africa, and 24 other countries. Facebook has deployed it in collaboration with local wireless carriers, and 15 million people are using it. But the app has received pushback on multiple grounds, particularly for offering only certain curated services rather than the full, unbridled Internet—a violation, critics say, of net neutrality principles.