Five classic Rook versions available for play: (1) Tournament Rook (a.k.a. Kentucky Discard); (2) Partnership Rook; (3) 1-High Partnership Rook; (4) The Red 1; (5) Buckeye. Each Rook version is available under the Settings tab. Rules of Play are provided under the Information tab.

CrowsNest is the app developer's favorite version of Rook, and is the default upon installation. It is identical to Tournament Rook, with two strategic exceptions: (1) the Crow card is the lowest trump; (2) when declarer's team achieves the bid they receive the bid amount, not total points captured.

CrowsNest is a partnership card game for 4 players, "We" team vs. "They" team. You and your AI partner (top of screen) are the We team. AI Opponents Left and Right form the They team. All 3 AI players have identical "skill". The winning difference is up to you!

The CrowsNest card deck consists of 4 suits identified by color, plus a "Crow" card which is always the lowest "Trump" card. Each suit contains cards numbered 5 thru 14. The 5's (5 points), 10's (10 points), and 14's (10 points) are "Counters", creating 25 points per suit. Additionally the Crow card is worth 20 points, making a total of 120 points in the deck. (The Crow card can optionally be removed from the deck, in which case there are 100 points.)

1. Play begins by sequentially dealing the cards, 9 to each player and 5 to the "Nest" (4 if the Crow card is not used). Player to the left of the "Dealer" begins the "Bid" process by committing to a total his/her team will capture of the 120/100 points available. Minimum opening Bid is 70 and subsequent Bids must be in multiples of 5, up to 120/100. Players may "Pass" at any time, but then cannot re-enter bidding. Bidding continues until all but one player has passed. If all players pass on the opening round the cards are re-dealt by the same Dealer.

2. Player with the highest Bid (the "Declarer") temporarily adds the Nest to his/her hand, and then discards back into it any 5/4 cards from the combined hand. Counters discarded into the Nest are added to the score of the team that captures the last "Trick" of the hand. Finally, Declarer chooses the "Trump" suit for the hand now to be played. If in use, the Crow card becomes the lowest Trump card.

3. Player to the left of the Dealer leads a card to begin the first Trick. Play continues clockwise around the table to the remaining 3 players. Players must play a card of the lead suit when they have one, except the Crow card may be played at any time. Players out of the lead suit are free to play any card. Highest card in the lead suit wins the Trick, unless card(s) of the Trump suit have been played. In that case the highest Trump card wins the Trick. Player winning the Trick captures the value of any Counters for his/her team, and leads a card to begin a new Trick.

4. After all cards have been played the hand ends. Counters in the Nest are added to the team winning the last trick, and Trick points won by each team are tallied. Team that opposed the Declarer receives the total of their points. If Declarer's team achieved or exceeded the Bid they receive the amount of their Bid. However if Declarer's team total falls below the Bid, they receive no credit for points won and the Bid amount is deducted from their score.

5. The deal now passes to the next player on the left, and a new hand is played by repeating steps 1-4.

First team reaching 300 points wins the game. If both teams have 300 or more points, the team with the most points wins the game. If teams have identical scores in excess of 300, a sudden-death hand is played to determine the winner.