Earlier this year Khan Academy released an iPad app that allows students to download videos to watch offline as well as sign into their accounts to track their progress on practice activities.
On Friday Khan Academy updated their iOS app to include support for accessing the Khan Academy catalog and watching the videos on your iPhone. The difference between the iPad app and the iPhone app is that on the iPhone you can only watch videos when you have an internet connection whereas the iPad app allows you to download the videos.
Applications for Education
The updated Khan Academy iOS app could be useful for students who have iPhones and need to access some videos to review a concept before a test.