This app offers 20-minute treadmill workouts designed to maximize results using science-based heart rate variability training. It provides guided sessions for weight loss, fitness, and performance, making cardio more efficient and engaging.





204+ iOS apps curated and reviewed
Out of 204+ zones cardio apps on iOS, 18 are free and the rest sit in the paid tier. This page sorts them so you can compare both sides before you commit.
| # | App | Price | Rating | Ads | In-App Purchases | Updated | |
|---|---|---|---|---|---|---|---|
| 1 | Free | 5.0★ (2) | No | Yes | Sep 2026 | ||
| 2 | Free | 4.8★ (19K) | No | Yes | Sep 2026 | ||
| 3 | Free | 4.4★ (1.1K) | No | Yes | Sep 2026 | ||
| 4 | Free | 4.6★ (13K) | No | Yes | Sep 2026 | ||
| 5 | Free | 2.0★ (1) | No | No | May 2026 | ||
| 6 | $1.99 | — | No | No | May 2026 | ||
| 7 | $49.99 | 4.3★ (40) | No | No | Jun 2026 | ||
| 8 | Free was $4.99 | 4.6★ (241) | No | Yes | Sep 2026 |





This app offers 20-minute treadmill workouts designed to maximize results using science-based heart rate variability training. It provides guided sessions for weight loss, fitness, and performance, making cardio more efficient and engaging.






This app helps you optimize your workouts by monitoring exercise intensity and visualizing it through heart rate zones. It supports over 70 workout types and provides detailed insights into your performance, all accessible on your Apple Watch and iPhone.






This app uses your heart rate to personalize workouts, optimizing calorie burn and performance. Earn points for effort in high-intensity zones and track your progress in real-time with connected devices.