Fitness tracking accuracy varies more between devices than most marketing suggests, and the right choice depends heavily on what you’re actually training for. This guide breaks down the current market by use case rather than by brand.
For sleep and daily activity: prioritize comfort and battery life
If your main goal is understanding sleep quality and daily movement patterns rather than structured training, a smaller, lighter device with multi-day battery life — like the Pulse Loop — will serve you better than a feature-heavy sports watch you’re tempted to take off at night to charge.
For structured training: prioritize GPS and sport-specific modes
Runners, cyclists, and swimmers training with specific pace or distance goals need standalone GPS and sport-specific tracking profiles, as covered in our Pulse Loop vs Pulse Band comparison. Battery life becomes a secondary concern compared to tracking accuracy during this kind of training.
Heart rate accuracy: know the limitation
All wrist-based optical heart rate sensors lose some accuracy during high-intensity interval training when heart rate changes rapidly. If precise heart rate data during intervals is critical (for example, for a coached training plan), a chest strap paired with any smartwatch will outperform wrist-only tracking regardless of brand.
Battery life expectations by device type
As a general rule: devices with built-in GPS and always-on displays last 2-4 days; devices without GPS and with a standard display last 5-7+ days. Choose based on which trade-off matters more for your routine rather than headline battery claims alone.
Frequently asked questions
Do I need a smartwatch with built-in GPS?
Only if you regularly exercise without your phone. If your phone is always with you during workouts, phone-based GPS tracking is accurate enough for most people and saves significant battery life on the wearable itself.