About the FlipSight Opening Book

The FlipSight opening book now contains about 4.62 million fully searched positions.

Until now, there was no way to tell on the board whether a book move had been fully searched.
Fully searched book moves now show a green check on the book icon.

In the position above, F3, F4, F5 and F6 are fully searched book moves, and F2 (-12) is a regular book move.

Book moves that are not fully searched were evaluated only up to a limited depth.
If the engine searches deeper than that, the book icon disappears and the engine's evaluation is shown instead.
Fully searched book moves always keep their book value, regardless of the engine search.

I hope this helps you get more out of the book!

Thank you.