The Apple Watch can offer inconsistent power consumption while tracking workouts, particularly during outdoor activities like cycling, according to a handful of complaints received by AppleInsider and seen on Twitter.
Apple officially states that the Watch should be able to last up to 6.5 hours under non-stop workout conditions. In many real-world cases the device is close to that mark, but in some instances users said their wearable has fallen well short.
One AppleInsider reader noted that he was able to get just two hours of battery life while cycling. Most Twitter comments appear to praise battery life during exercise, but one example from Twitter mentions power dropping 13 percentage points in 34 minutes of activity.
Another cyclist said his Watch fell to 29 percent after a little over three hours and 15 minutes of riding.
One of biggest drains on the Watch during a workout is the heart rate sensor, which flashes rapid visible or infrared light pulses to monitor blood flow. Apple in fact offers a "Power Saving Mode" in the Workout section of the Apple Watch iPhone app that will force less intense tracking. Users who are experiencing poor battery life during workouts should try this setting to extend uptime.
Outdoor exercises are likely imposing extra drain since they ideally use a paired iPhone's GPS to calculate distance. The Watch has built-in motion sensors, but these are less accurate for distance measurements.
Apple estimates that under regular conditions, the Watch should last 18 hours on a charge, including a 30-minute workout with on-device music playback, and 45 minutes of app use.