Tap the mic and say a move: "pawn to e5", "d7 to d5", "right knight to c3", "castle kingside". Left and right are as you see the board. Speech is recognized by your browser; Chrome sends the audio to Google to do it.
Ring around a piece: one slice per legal move, best to worst going clockwise from the top. ★ marks every piece that has a Best-rated move, and every Best-rated target of the selected piece. On a selected piece's targets, the arc fills to your winning chance after that move (when there's a forced mate, mating moves fill more than half the ring, the quickest filling all of it, and every other move fills less than half); the number is the engine score in the standard convention: + is good for White, − for Black (so as Black, lower is better for you).
Badges mark a fork, pin, skewer, discovered attack, trapped piece, removed defender, overloaded piece or sound sacrifice the move forces, either right away or after the opponent's best reply in the engine's line. Purple means the tactic works: the move is rated Best or Good and the engine's line wins material. Red means the move sets it up but it doesn't pay off. Purple arrows show your tactic, red arrows what the opponent gets, blue arrows book moves.