Here is a good news for students who own Android devices. Khan Academy application beta is available for Android devices
Khan Academy is a non-profit educational organization created in 2006 by educator Salman Khan to provide a free, world-class education for anyone. It covers a wide range of subjects such as Mathematics, biology, chemistry, economics, art history and almost anything for free. It can help you to prepare for the upcoming SAT, GMAT, or MCAT exams too.
Here is how you can get the Khan Academy App from the Google Play store
- Join this community: https://plus.google.com/u/0/communities/115871747698269443910?cfem=1
- Click the "become a tester" button: https://play.google.com/apps/testing/org.khanacademy.android
- Download the app (it can take a 10-20 minutes after becoming a tester for access to the link to work - let us know if you're having further problems): https://play.google.com/store/apps/details?id=org.khanacademy.android
If you own an iOS device, the application is already available on the iTunes and you can get it Khan Academy: learn math, biology, chemistry, economics, art history and almost anything for free