Khan Academy, the wildly popular YouTube lecture series, has launched its free, new iPad app in Apple’s store. The enhanced version of Khan Academy includes time-syncing between devices–no Internet connection required–an interactive transcript of the lectures for easy searching, and a handy scrubber for moving between parts of the lectures. Perhaps more importantly, now that more schools have begun adopting Khan’s lectures for their own classrooms, the iPad app could possibly replace or supplement textbooks, saving cash-strapped schools and students a lot of money.

The major benefit of the app is offline learning. “If you’re going on a road trip or if you’re taking mass transit and you don’t have cell service, or whatever, you can get the content,” says Khan Academy Lead Designer Jason Rosoff. The iPad frees Khan Academy from the constraints of a laptop and Internet connection. Rosoff says the app will remember where users left off viewing and sync progress between devices (though, for the initial version, both devices will need to connect to the Internet before going offline to sync).

Second, with inspiration from TED, Khan lectures will now have an interactive time-stamped transcript, which is a convenient search function, considering some of the lectures can be quite long.

Last, just like a textbook, users flip back and forth between different parts of the content. “People scrub a lot in our videos,” says Rosoff. The app will have an enhanced version video scrubber (the scroll bar at the bottom of a video) that makes repeating areas less painful.