I really like the videos offered with this app, helped me learn some good Openings. Easy to navigate and find what I need.
The app has been improving since newer updates. App ran sluggish before, but is running smoother. I have a iPhone 4 so this matters a lot for my hardware.
The opening book chess book needs navigational keys like play button, rewind and forward. Its a little hard to move through piece moves. I am sure this isnt much of a problem with a iPad.
Other than minor things, this is a really good App to have to learn openings. The videos are well worth it.
Raven_2012 about Chess Openings by ChessOpenings.com