blog:

“A free, world-class education for anyone, anywhere.” This mission inspires us day in, day out, and we’ve seen over 30M students sign up on Khan Academy to learn almost anything for free. We know you love using Khan Academy more and more on your phones: in fact, over 30% of our sessions are now on mobile devices. We believe strongly that unlocking the potential for anyone, anywhere to learn on 2B+ smartphones worldwide is just getting started. Today, we’re excited to announce a couple steps toward a better Khan Academy in your pocket!

Khan Academy on Android and iPhones