Chest Strap HR Monitor

Turtle Tunes Studio

In-app purchases

About this app

Strap Zone connects your Bluetooth heart rate chest strap directly to your phone — no smartwatch required. See your heart rate zones in real-time and train smarter.

Strap Zone Pro starts with a 7-day annual trial. Prefer paying once? A lifetime unlock is available too.

SIMPLE HEART RATE ZONE TRAINING
Just heart rate zones and workouts, with optional GPS route export when you want it. No social features, no complicated coaching. Connect your chest strap, start your workout, done. The simplest heart rate monitor app for your phone.

LIVE HEART RATE MONITOR
Big, readable BPM display that's easy to see during any workout. Watch your heart rate update in real-time with color-coded zone backgrounds.

HEART RATE ZONES (Z1–Z5)
See your current training zone instantly:
• Zone 1 — Recovery
• Zone 2 — Endurance & Fat Burning
• Zone 3 — Tempo
• Zone 4 — Threshold
• Zone 5 — VO2 Max

Use zone 2 sessions to organise steady aerobic training. Audio alerts tell you when your measured heart rate leaves the target zone, so you do not need to watch the screen.

STRUCTURED WORKOUTS
Build custom workouts with target heart rate zones, timed segments, and repeat blocks. Ideal for HIIT heart rate training, threshold intervals, or guided zone 2 cardio sessions.

TIME-IN-ZONE TRACKING
See exactly how long you spent in each heart rate zone during and after your workout. Track your fat burning zone time, endurance zone time, and more.

WORKOUT HISTORY
Review past sessions with detailed zone breakdowns and heart rate data.

OPTIONAL HEALTH CONNECT EXPORT
Off by default. If you opt in, Strap Zone can write your completed workouts and the recorded data you select to Health Connect: heart rate, estimated active energy, distance and GPS route, when system permissions allow. Strap Zone never imports health data from other apps.

GPS ROUTE + TCX EXPORT
Optionally record route, distance, pace splits, and export a complete TCX file for platforms like Strava, Garmin Connect, and TrainingPeaks. GPS can be turned off anytime in Settings.

COMPATIBLE BLUETOOTH HEART RATE SENSORS
Strap Zone is designed for sensors that broadcast the standard Bluetooth Low Energy Heart Rate Service. Compatibility is model-specific. Our public evidence matrix documents the current status for Polar H10, Garmin HRM-Dual, Wahoo TICKR and other named models:
https://strapzone.app/compatible-heart-rate-monitors/

No smartwatch needed. Connect a compatible heart rate strap directly to your phone.

CUSTOMIZABLE HEART RATE ZONES
Set your personal HR Max for accurate zone calculations. Editable zone boundaries let you customize for your fitness level and training goals.

PRIVACY FIRST
No account required. No heart-rate or GPS route data leaves your device unless you explicitly enable an export.

Perfect for runners, cyclists, gym workouts, indoor cycling, treadmill training, rowing, CrossFit, or any activity where you want to monitor your heart rate zones without wearing a smartwatch.

Train in your zones. Train smarter.

What’s new

Choose your workout data in settings.
• Preview and show or hide calories, time in the current zone during free workouts, distance, and pace or speed.
• Add your weight to enable estimated active calories.
• Your current layout stays the default. Movement data appears when GPS is on and your activity supports it. Restore defaults at any time.