Prior: Calibration Trainer

Prediction tracker & journal

Free · In‑App Purchases · Designed for iPad. Not verified for macOS.

Most people think they're better at predicting than they are. Prior shows you the data. Track predictions, measure accuracy, compete globally. 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/

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The developer, Brandon Wang, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Linked to You

    The following data may be collected and linked to your identity:

    • Contact Info
    • Identifiers

  • Data Not Linked to You

    The following data may be collected but it is not linked to your identity:

    • Usage Data

Privacy practices may vary, for example, based on the features you use or your age. Learn More

Accessibility

The developer has not yet indicated which accessibility features this app supports. Learn More

Information

Seller
  • Brandon Wang
Size
  • 51.1 MB
Category
  • Trivia
Compatibility
Requires iOS 15.1 or later.
  • iPhone
    Requires iOS 15.1 or later.
  • iPad
    Requires iPadOS 15.1 or later.
  • iPod touch
    Requires iOS 15.1 or later.
  • Mac
    Requires macOS 12.0 or later and a Mac with Apple M1 chip or later.
  • Apple Vision
    Requires visionOS 1.0 or later.
Languages
  • English
Age Rating
4+
In-App Purchases
Yes
Copyright
  • © 2026 Brandon Wang
  • Privacy Policy