Testify - A/B testing tool

​Testify lets you run real experiments on your everyday life. Wondering if that new supplement actually helps your workout? Curious whether your morning routine affects your productivity? Stop guessing and start testing.

Set up an experiment with a hypothesis, track your results day by day, and let Testify crunch the numbers. The app automatically picks the right statistical test for your data — Chi-Squared for yes/no outcomes, or a Two-Sample T-Test for measurements — and tells you in plain language whether your results are meaningful or if you need more data.

Features:

- Create experiments with a hypothesis and a variable to test
- Record trials with date, time, results, and optional contextual notes
- Automatic statistical analysis with Chi-Squared and Welch's T-Test
- Optional Bayesian view showing the probability one variant is better, with a 95% credible interval
- Sequential analysis with a Pocock boundary so repeated peeking doesn't inflate false positives
- Visual charts comparing your control and treatment groups, with a best-fit trend line for numeric experiments
- Confidence intervals so you can see the range of possible effects
- Post-hoc statistical power analysis
- Sample size estimates that tell you how much more data you need
- Plain-English explanations of your results — no stats degree required
- Share polished result images with friends or social media
- Daily reminders to log your data, with deep links straight to the experiment
- Edit experiments and trials at any time, conclude or reopen as your investigation evolves
- Track multiple experiments at once with a last-viewed summary card
- Home screen widget showing your most recent experiment and a one-tap Add Trial shortcut
- First-launch walkthrough to get you started quickly
- Light and dark mode support

Testify Pro (optional subscription):

- Unlimited experiments
- CSV import and export for your trial data
- Multi-page PDF report export with charts, summary, and trial table

Whether you're optimizing your sleep, testing a new diet, or settling a debate with yourself, Testify gives you the tools to find out what actually works.

Get it on the App Store!