The free version has some restrictions, it just works with 6BB or less stack sizes. Download pro version to eliminate this restriction.
The Nash equilibrium, game theory basis, widely employed in numerous fields, is very useful when utilized in Poker.
In the book "The Mathematics of Poker", their authors developed a couple of charts
based on the Nash equilibrium, which describe the "equilibrium play".
By following this strategy, our game becomes unexpoitable, i.e. no matter how our opponent plays, he won´t be able to take advantage of us.
This strategy is used by many Poker players, including the Poker pros.