Six of the best fitness trackers, from bargain to big-budget options

For Android users only, this has 24/7 fitness tracking, automatic sleep and heart rate, stress and blood-oxygen monitoring; plus built-in GPS and a body composition feature. Battery life is 24 hours.

The latest Apple smartwatch has a heart sensor, an ECG and blood-oxygen monitor, plus basic workout challenges. Battery life is 18 hours, and the display features a full keyboard.

Weighing just 28g, this has a colour AMOLED touchscreen, an ECG app and an EDA Scan app for stress manage­ment, plus sleep tracking. Battery life is up to seven days.

Weighing 29g, this running watch has a 30-hour battery life in full GPS mode (that stretches to 20 days if used for just heart rate, sleep and step tracking). Great value, and it has 16 built-in modes.

This self-powered smartwatch never needs charging. It displays heart rate and step count, and, via an app, provides GPS tracking and sleep and blood oxygen levels.

Aimed at triathletes, this multisport smartwatch has “touchless transition”, which can tell when you change discipline. 14 days battery life, or 24hrs in GPS mode.