Schwimmen HD is a mobile game developed by SITDZenith. It is a classic card game that is popular in Germany and Austria and is also known as "Schnautz," "Knack," "Hosen runter," or simply "31." The objective of the game is to collect cards in a single suit worth 31 points or as close as possible to that total.

The game is played with three cards dealt to each player and three more cards dealt in the middle of the table. Players can only combine cards of the same suit. The game offers four options every turn: swap one card of your hand with one of the face-up cards on the table, swap all your cards with the three cards on the table, pass, or end the game.

Schwimmen HD has three difficulty levels: Easy, Normal, and Hard. It also has special combinations like "Feuer," which is worth 32 points, and "Three of a kind," which is worth 30.5 points. The game has amazing HD graphics, gorgeous animations, and simple controls. Players can choose the number of decks and players, the difficulty level, and unlock different backgrounds and card sets as they play. The game is optimized for mobile and tablets, making it accessible to everyone.