NTest[1] is a free Othello/Reversi program created by Chris Welty (not to be confused with the other computer scientist named Chris Welty who worked on the IBM Watson project).
NTest is a strong Othello program with a high-quality evaluation function and fast search algorithms. It has many features, with the most important one being the display of the search evaluation for all possible moves.[2] NTest is among the strongest programs in the world. It is able to dobitboard-based move generation and parallel searches on multipleCPU cores.
Other programs' opening books—such asEdax's book—can be used in NBoard, the GUI created by Chris Welty for NTest.[3]