Product Price Heart Rate Monitor Step Counter Calories Burned Sleep Tracking Activity Tracking Battery Life (hours) Waterproof Rating
Polar H10 Heart Rate Monitor (chest strap)
US
£78.63 Up to 400 hours 30 m

Polar H10 is a chest-strap ECG heart rate sensor offering high-accuracy heart rate data with Bluetooth and ANT+ connectivity, internal memory for one training session, and swim-safe 30 m water resistance. It suits athletes and swimmers who need precise heart-rate recording and multi-device pairing.

Apple Watch Series 11
US
£298.93 Yes Yes Yes (workouts, activity rings, automatic workout detection) Up to 24 hours 50m

The Apple Watch Series 11 offers advanced health sensors including optical and electrical heart sensors, blood oxygen, sleep-stage tracking, and comprehensive workout and activity features. It suits users who want a high-end smartwatch for fitness, health monitoring, and everyday connectivity.

WHOOP WHOOP 4.0
US
£179.06 Yes (calories tracked) Yes (strain and activity detection; manual workout logging available) up to 5 days water-resistant to approximately 32 feet for two hours

WHOOP 4.0 is a screen-free wearable focused on continuous biometric monitoring: heart rate, HRV, sleep, strain, and recovery, delivered through the WHOOP app and a subscription. It suits athletes and users who want in-depth physiological insights and coaching rather than smartwatch features.