About this app
Most people think they're better at predicting the future than they actually are. A perfect predictor knows the quality of their predictions, and you can rely on their 80% forecasts to be right exactly 80% of the time. This skill is called calibration. THE ENGINE An infinite question bank spanning science, economics, technology, history, sports, and culture. For every question, you don't just answer true or false; you state how confident you are. That confidence is what Prior measures. Binary mode tests your true/false predictions with a confidence slider. Continuous mode (Prior Pro) asks you to estimate ranges - the harder, more revealing challenge that separates calibrated thinkers from lucky guessers. THE CALIBRATION CURVE Your calibration curve is the most honest thing about you. It shows whether the things you believe with 80% confidence actually happen 80% of the time. Most people are overconfident at high confidence levels - their curve bends away from perfect. Prior makes that visible. THE JOURNAL Track your real-world predictions - markets, elections, sports, personal decisions. Set a resolution date, state your confidence, come back when the answer is known. Your journal builds a permanent record of your forecasting history, scored alongside your engine training. THE LEADERBOARD Compete globally against other forecasters ranked by Brier score. PRIOR PRO Unlimited continuous (range estimate) questions, full calibration curve with domain breakdown, Brier trend over time, confidence distribution analysis, unlimited journal predictions, and a Pro badge on the global leaderboard. Free users get unlimited binary training, basic stats, and up to 10 active journal predictions. PRIVACY No advertising. No data sold. Optional account for leaderboard access - anonymous training requires no sign-in. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/
Audience growth
Ratings growth
Baseline captured. Growth appears after the crawler observes a changed rating count.
Momentum comes from crawler snapshots for the tracked storefront. “Viral growth signal” means unusually fast recent rating gains; it is an indicator, not download data.
Price tracking
Price intelligence
First snapshot captured. The trend line starts after the next crawler price observation.
- First observed Aug 16, 2026 · 7:30 PM Free
Screenshots
