About this app
Peak Intervals helps you train VO₂max using the Norwegian 4x4 interval method and track training quality over time. Run, ride, or row a 4x4 session, stay in your target heart rate zone, then review clear metrics that explain workout quality and progress over time. What you get: • Guided 4x4 workouts with Apple Watch support • Target heart rate zone guidance based on 90–95% of estimated HRmax • Time in Zone (≥90% HR) to measure intensity • Repeatability to see if you hold performance from interval 1 to 4 • Recovery to measure how fast your heart rate drops between intervals • Trends and simple verdicts like Improving, Stable, Under-target, or Fatigued • Workout history with interval breakdowns and session details Apple Health Peak Intervals can read workout and heart rate data from Apple Health (HealthKit) to compute your metrics and trends. You control what is shared at any time in iOS Settings. Subscriptions Peak Intervals offers an auto-renewing subscription with monthly and yearly plans, including a 2-week free trial where available. After the trial, an active subscription is required to start new workouts. Payment is charged to your Apple ID account at confirmation of purchase. Subscriptions renew automatically unless canceled at least 24 hours before the end of the current period. You can manage or cancel your subscription in App Store account settings. Peak Intervals is not a medical device and does not provide medical advice. High-intensity exercise may not be appropriate for everyone. Consult a physician before beginning a new training program. Privacy Policy: https://peakintervals.app/privacy Terms of Use: https://peakintervals.app/terms
Latest release
What’s New
• Redesigned onboarding — try the app right away, no account required • Full localization: German, Spanish, French, Italian, and Portuguese • Fixed mixed-language UI by following your per-app language setting • Improved Trends and workout metrics • Bug fixes and stability improvements
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 Sep 8, 2026 · 3:59 AM Free
Screenshots
