Vita Mahjong can be a calm game, but calm games can still take more time than planned. The key is to keep the session intentional.
Before opening Vita Mahjong, decide whether you are playing one board, a short break, or a longer planned session. Use Sandflow to keep the session timer visible and Screen Time to set the daily ceiling.
Stop at the end of a board. Do not let the next layout decide for you.