Make24

The 24 game is a mental arithmetic puzzle: take four numbers and use +, -, x and / to finish on 24. Make24 turns it into one numbered puzzle a day. You tap a number, choose an operation, then tap another number, and the result replaces the two you used. Keep combining until a single 24 remains. Every starting number has to be used exactly once, and division only counts when it gives a whole number.

The timer starts on your first tap. The app records your solve time, streak, fastest and average times and a history of past puzzles, and you can compare times on Game Center leaderboards and earn achievements. A share button posts your result without giving away the route. If you missed yesterday's puzzle, you can reveal its solution and see the steps.

The developer's site says everyone gets the same four numbers each day, and each daily puzzle is chosen to have at least one valid route to 24. Make24 is made independently by Stuart Malcolm and came to the App Store at the end of 2025. It is free with ads, with optional ad-free subscriptions and tips.

The Make24 website has a practice board that plays in any browser: four random numbers, the same tap-and-combine controls, and a New puzzle button for as many rounds as you like. The shared daily puzzle itself is only in the iPhone and iPad app. The site also has a strategy guide and resources for teachers who want a quick mental maths starter.