Prime Time

For iPhone and Apple Watch · Available now on the App Store

A number appears. Is it prime? Answer, learn a fact about the number, and see how long your streak can last.

Download on the App Store

Prime Time asking whether 31 is prime, with Prime and Not prime buttons

A correct answer for 31, with the fact that 31 is a Mersenne prime

Game over screen showing a streak of 5 and a New Best badge

One wrong answer ends your run, and your best streak is saved.
Works entirely offline, with no accounts, tracking or ads.
Built to work well with VoiceOver and Dynamic Type.

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