EvoDyn-3s: A Mathematica computable document to analyze evolutionary dynamics in 3-strategy games. EvoDyn-3s generates phase portraits of evolutionary dynamics, as well as data for the analysis of their equilibria. The considered evolutionary dynamics are ordinary differential equations based on adaptive processes taking place in a population of players who are randomly and repeatedly matched in couples to play a 2-player symmetric normal-form game with three strategies. EvoDyn-3s calculates the rest points of the dynamics using exact arithmetic, and represents them. It also provides the eigenvalues of the Jacobian of the dynamics at the isolated rest points, which are useful to evaluate their local stability. The user only needs to specify the payoff matrix of the game and choose the dynamics.