Tactica: Chess Tactics Trainer

Most puzzle apps hand you a random position and move on. Tactica works out which tactical patterns you keep missing, then drills those until you stop missing them. *ADAPTIVE DIFFICULTY Every puzzle is rated, and so are you. Tactica serves puzzles at the difficulty where you succeed about three times in four — hard enough to learn from, easy enough to keep going. * IT FINDS YOUR BLIND SPOTS Forks, pins, skewers, deflections, back-rank mates. Tactica keeps a separate rating for each of nearly thirty tactical motifs. When one falls behind, it says so plainly: "Your deflection rating is 1,290 — 180 below your overall 1,470." Then it feeds you more of them. * PUZZLES COME BACK BEFORE YOU FORGET THEM Miss one and it returns days later, timed for when you are most likely to have forgotten it. Solve one cleanly first time and it never returns — there is nothing to relearn. * EVERY PUZZLE…