Your iPhone already tracks your health. N of 1 helps you see which habits actually make a difference — sleep, supplements, exercise, and more.
How It Works
Create an experiment in a few taps. Your phone collects the data automatically. Check in daily or just wait for the results.
Pick what you want to test — a supplement, sleep change, workout routine. Choose how long to track. That's it.
N of 1 uses your existing Apple Health data. No extra tracking, no manual logging. Just live your life.
When your experiment ends, you'll see exactly what changed. Check the app or wait for the notification.
Your Experiment, Your Rules
Run one experiment at a time. Change one thing. See what happens. Control for variables like a (slightly) disciplined adult.
Change your whole life at once. New sleep schedule, no caffeine, cold showers, magnesium. Who needs controls? Not you.
What You Get
Connects to your existing Apple Health data. Sleep, heart rate, steps, weight — it's all there already. No extra tracking required.
Pick what to test, pick how long, done. Your phone handles the rest automatically.
Get reminded to check in, or just let it run and get a notification when your results are ready.
Get plain-English results. What changed, by how much, and what it probably means. No stats jargon.
Day-by-day charts showing your before and after. Easy to scan, easy to understand.
As many experiments as you want. Test everything at once or one thing at a time. Your call.
Privacy First
We designed N of 1 from the ground up with a simple rule: your data never leaves your device.
All data is processed and stored locally in SQLite on your device. We don't have a backend that touches your health data.
We don't embed ad SDKs, usage trackers, or any third-party analytics that could see your health information.
N of 1 never writes to Apple Health. It only reads the data you've already collected, using Apple's standard permission system.
One tap in Settings permanently deletes every experiment, result, and note from your device. No cloud backup to worry about.
* AI Insights (Premium) sends anonymised statistical summaries to a third-party AI provider. Raw health data never leaves your device. See our Privacy Policy for details.
Simple Pricing
The free version has everything you need to run experiments. Premium adds easier results and unlimited tests.
Cancel anytime in the App Store. No tricky contracts.
Why N of 1
Your Apple Health data is already tracking everything. Let N of 1 help you see what it means.
Download on the App StoreFree to download · iOS 15+ · Requires Apple Health