I built a quiz app where grinding doesn't work — soft launching in 8 hours

Been building Cerebro for the past few weeks and we go live on Product Hunt in 8 hours.

The core idea: most quiz apps let you brute-force your way to the top. Play enough and you'll rank. Cerebro uses a rolling IQ rating — accuracy and speed, not volume. The only way up is to genuinely get better.

A few things that surprised me during beta:

— The company leaderboard caused more drama than I expected. People care deeply about being the smartest person at their workplace.

— The displacement notification ("someone just knocked you off #1 in your country") has the highest re-engagement rate of any feature I've built. Turns out ego is a great retention mechanic.

— Players from Nigeria, UK, and India are currently dominating the global rankings. I did not predict that.

Dropping tomorrow. Would love follows so you don't miss it — and genuinely curious: what would make you play a quiz app every day?

🔗 cerebro-quiz.com | iOS: apps.apple.com/us/app/cerebro-the-hardest-quiz/id6761792205