Tile tracking or 'consonant-heavy', how many S's or blanks are unseen, if an opponent is likely to have a bingo on their rack, or which tiles to play or conserve. For example, if Alice has the option of playing J(I)NN or J(I)LL, and four N's and zero L's remain unseen, then assuming both plays are otherwise equal (in terms of score, openings for the opponent), J(I)NN is likely the better play. Letter frequency lists for both Scrabble and Words with Friends are easily accessible (some versions of Scrabble have the tile distribution directly on the board) and, unlike word lists, using them
Tile tracking player who can plan and calculate the best move while taking into consideration the other player's possible responses—winning a close game by blocking an opponent’s big play or setting up a high-scoring play the opponent cannot block. Scrabble champion John Holgate notes that tile-tracking is particularly important in tight "bobbing" finishes when the bag is empty, and that many games are lost through "just not knowing what tiles your opponent has on her rack. You simply cannot calculate possible permutations if you are unsure about which letters are relevant." Tracking can also tell a player if the bag is ‘vowel-heavy’