Castle Solitaire is a free Android game developed by yeterapps. It falls under the card game category and offers a unique twist on the standard rules for Pyramid or TriPeaks solitaire.

The game has a table with three towers behind the deck cards. To move a card, players must select one with a value of one point higher or lower than the top one, regardless of suit. The game offers two rounds, and if players complete the first round successfully, they will advance to the second one. Overall, Castle Solitaire is a fun and challenging card game that will keep players entertained for hours.