"The thing I always stress is people still see Khan Academy as me and videos," Khan Academy Founder and Executive Director Salman Khan tells Education Dive during a phone call one day removed from his closing keynote at SXSWedu 2015. "It’s now much, much more than me."

The nonprofit online learning juggernaut has grown from Khan creating math tutoring YouTube videos for his cousin in 2004 and its official launch in 2006 to a team of 80 with thousands of global volunteers behind its content. There's more than videos now (though that library reportedly exceeds 4,800), with adaptive exercises and other content now spanning the sciences, humanities, history, and beyond. There are also now Spanish, Brazilian Portuguese, French, and Turkish versions, with more languages on the way.

All this, and he plans on always keeping it free of fees and ads.

Here in the U.S., the platform has been lauded for its ability to reengage students who have fallen behind. In East Palo Alto's San Francisco 49ers Academy, where 95% of students are on free-and-reduced lunch, he tells us about one eighth-grader who was falling behind but is now ahead of his peers and entering algebra, currently holding the Bay Area's highest score for "grit" or perseverance on Khan Academy, as well. Even so, he concedes the improvement isn't all his platform's doing.

“Most of the credit goes to the teaching staff and students," Khan says.

Over the course of our conversation, we touched on these success stories, the future of Khan Academy, and when we might see an official Android release.

How was SXSWedu?

Oh, it was great. A lot of energy. This was actually the first time that I’ve spoken there, so it was really great to see, and I’ve been told that it’s been growing pretty dramatically.

Did you see or hear anything particularly interesting?

For me, it’s always actually the individual stories. Every time you give a talk or a presentation like this, there’s always the people who come up at the end and they talk about what’s happening at their schools. Actually, while I was there, I met a young woman who—I guess she had some neurological issues. In algebra, when she was in ninth grade, she got, like, a 13 on an exam. So she dropped out of that school and she went to another school that was heavily using Khan Academy, and that allowed her to get an A in algebra. Now she’s racing ahead and about to go to college. When I hear stories like that, that’s pretty exciting.

You recently released an official iPad app. What did you want to focus on in particular in that experience compared to other platforms? 

As you know, Khan Academy is often known, or has been known in the past, for its collection of videos—and that’s a big part of Khan Academy. But most of what we’ve invested in is interactive, adaptive, personalized software, where you get as much practice as you need and understand what your gaps are, what you need to work on.

In the past, that’s been primarily done through the web. That’s great, but you have to have kind of separate scratch paper, and you have to type in your answers. We always said what’s obvious about a tablet interface is you can do the work on the tablet. And wouldn’t it be amazing if it had handwriting recognition? You could literally write with your finger the square root of cosine of x, and it would just recognize it. That’s what this app does.

With the kids that I’ve observed, and actually even just using it myself, it’s a pretty transformational experience. I think it’s now kind of the flagship experience for using Khan Academy, because you just have to get a tablet out. It’s kind of like what we probably envisioned the future of education would look like. The kids are with the tablet and they’re able to do the questions right there, and it actually reads what they wrote and can progress them at the right time or pace.

With your global reach and Android’s status as the most widely used mobile OS in the world, is there an official app for that platform on the way?

It’s coming. It’s coming. Right after we did the iPad launch and we saw the success there and we saw the interest there, that’s the next thing down the pipeline. We're thinking very seriously about Android and mobile to reach students where they are.

With $4 billion in state and federal funds spent on remedial ed per year, how have you seen Khan Academy help in schools and districts on that front?

Even in the first year, when we did pilots in Los Altos, one of the classes that used it was a remedial math class. We are working with community colleges to understand how Khan Academy can be used for students who are looking to test out of developmental math or remedial math so they can get into the actual credit-bearing courses. We think that’s a big area. There’s a lot more that we need to explore to figure out what Khan Academy in particular can do, but we think there’s a lot of potential there.

You’re partnered with College Board. There's a push for assessments that break away from the current standardized model that’s largely quantitative in what it measures. In interviews, you’ve advocated for proof of critical thinking and formats like a portfolio. Do you see Khan Academy potentially having a bigger hand in developing a new way to approach assessment? What do you see that excites you on that front right now?

Traditional tests, they measure one dimension of you. They’re kind of a snapshot of your current knowledge, and an imperfect one at that. But, and I wrote a lot about this in my book, the other piece that would give a fuller picture of someone is examples of things they’ve actually created, their portfolio. This could be things they’ve written. It could be things they’ve programmed. It could be things that they’ve built or painted or composed, whatever it might be. That is pretty powerful. And then on top of that, some type of peer assessment: How much you have helped your peers, your ability to work with peers, things like that.

We have very nascent things on Khan Academy along those lines. We actually have a very deep computer programming platform where it really is all about creating your portfolio, and that also has a peer assessment component. So we’ve already taken some steps on the computer programming side on Khan Academy there, but I hope in the future, we can do some more things with writing or music composition or whatever else. I don’t think anytime in the very near future, we’re going to have an SAT-like, portfolio-based assessment—and our focus isn’t on the assessment side, it’s mainly on the learning and creation side—but these are things that we hold dear to our heart.

Is Khan Academy planning anything on the teacher professional development front?

We don’t have any formal, physical programs. We do have some resources where teachers, in an online way, can see examples of how Khan Academy has been used, how it can be used, or find context that may be appropriate for how they use it. So we do have an online version, but we don’t have a more traditional training program.