Hey Product Hunt!
I m building Numday, a daily mental math challenge for Android.
The core idea is simple: everyone gets the same chain of 7 calculations each day, has 90 seconds to solve it, and then compares scores in global rankings or private leagues with friends.
We made one product decision early: you can play first without creating an account. Sign-up only appears after you see your score and want to publish it or enter the leaderboard.
Give it a try! https://play.google.com/store/apps/details?id=com.kamisoft.numday