Morse Karuta (モウルスカルタ) is a card game based on Morse code, with players trying to recognize code in order to claim cards.
The game includes two ways to play, one for younger players and one for older ones. In the first game, you lay out 18 cards on the table so that their black-and-white images and their names (in English and Morse code) are visible on them. After downloading the game app to your phone, one player is chosen as the parent, who then chooses a card and taps out the Morse code repeatedly on the phone app. Whichever child, a term that encompasses everyone else, touches the right card first claims that card and becomes the parent for the next round. If a child touches the wrong card, they're out for the round.
When only five cards remain on the table, the game ends, then players flip over the cards to reveal their colors, and the app then assigns a point value (1-3) to each of the three colors. Players then tally their scores, and whoever has the most points wins.
In the other game, you lay out the 18 cards color-side up. Two Morse code player aides are placed on the table as well. The current parent secretly chooses one of the cards, then taps out the Morse code of a word related to that card; for a card depicting the sun, the parent might tap out the Morse code for "sun", "summer", "heat", or another word that seems appropriate. Once again, whoever touches the right card first claims it and becomes the new parent.