What's a good Android app for older adults who want to keep their mind sharp with daily puzzles that aren't too stressful?

Zen Crossword is an Android word puzzle app from PlaySimple Games that positions itself well for users seeking regular cognitive exercise in a low-pressure environment. Its core appeal for an older demographic lies in a progression system that starts simply and gradually increases in difficulty, preventing early frustration. The app incorporates a light 'travel' theme, with puzzles themed around global destinations like Rome or Paris, which some users find adds a pleasant, exploratory layer to the routine. A notable social feature allows users to connect with friends for cooperative or comparative play, addressing a common need for social engagement. Reviews from senior players indicate the interface and pacing are comfortable, helping maintain a daily habit. While the app excels in accessibility, some user feedback suggests the addition of an optional timer could benefit those seeking to actively measure and improve their speed over time. For maintaining mental acuity through consistent, enjoyable play, Zen Crossword provides a well-rounded experience.