Filmmaker Ken Burns is famous for creating compelling documentaries on all things America, and now there is an iPad app that brings a huge amount of that content to your tablet in an interesting interface for exploring the past. The app is simply called Ken Burns, and it's free to try.

The app has an interface that is undeniably attractive, but it's not entirely clear how to work it at first. It's a timeline with circles representing video segments about each event on the timeline. You can tap on any one of them to view the video, or pull up full documentaries containing it. Thankfully, the app pops up some tips on getting when you've investigated a little.

Drag any of the events up to get the playlist it is a part of, or drag down to get the actual documentary the video it is packaged with. So for example, if you drag Pearl Harbor up, you get the warfare playlist. Drag it down and the app reveals the World War II documentary. It's just assembling the videos contained in the app differently.

The app is only 24MB, so the video is being streamed from a server someplace. That's great if you're low on storage space, but not so good if you don't have an internet connection. That said, the video quality (and obviously, the production values) are great. The app even does a neat parallax shift when you tilt the device, just like the home screen in iOS 7.

The Ken Burns iPad app comes with the Innovation playlist for free. It contains content about Lewis and Clark, railroads, and broadcasting—it's about 30 minutes of video. If you want access to everything, it will cost you $9.99 via an in-app purchase.