App engine integration

How far are we from an app where diagrams are shown and we can not only play main and alternative lines but even break off and play our own truncated games against a houdini engine say 20 moved on from the diagram.

What about chess puzzles not having to move the pieces yourself but having a houdini engine play you adversarially so that you unlock the puzzle with perfect play and fail if you don't find the right moves.

Why doesn't this already exist as well? I feel like in general chess app software is so much more primitive than what it can be if people got their act (euphemism) together

I should have mentioned this is for the ebook apps that have been popping up recently

Strange. I am developing a similar app as a summer project. The full idea of the app of course cannot be disclosed but am hoping to put it out on the market soon.

I really hope someone doesn't finish it before I do.

If you're creating an app similar to the one I described would you also be able to gather all the great chess books for which the copyright has lapsed and offer them as interactive ebook titles with engine integration?

An integration of them as a readable PDF format would be three lines of code (and some gathering)

However, the tougher task is to convert the ideas contained in those books to something more interactive. That would require myself reading the book and creating little puzzles for the readers to get the idea behind each opening etc. Lots of work but doable.