Smartwatches

What decides the choice

The two specifications that separate running watches are GPS accuracy and battery life, and they are directly connected — which is why watches that are excellent at one are often mediocre at the other.

Dual-band, sometimes called multi-band, means the receiver uses two satellite frequencies instead of one. That lets it reject signals that have bounced off a building before reaching your wrist. In open countryside the difference is negligible. In a city it is the difference between a track that follows the road and one that wanders through the buildings beside it. If your running is urban, this is the single specification worth paying for.

Battery figures are quoted per mode and the modes are not comparable between makers. "Smartwatch mode" means the watch is not recording an activity; "GPS mode" figures drop sharply, and dual-band drops them further still. Compare GPS-mode numbers with GPS-mode numbers, and treat the headline smartwatch figure as marketing.

Screen technology is the trade behind both. AMOLED looks dramatically better in a shop and costs battery. Memory-in-pixel screens look worse indoors, are readable in direct sunlight without a backlight, and are the reason some watches quote two weeks instead of five days. Neither is better; they are different answers to the same question, and you should decide which side you want before you look at a display.

One thing worth checking before you buy anything in this category: whether the training metrics require a subscription. Several makers now put recovery and load analysis behind a monthly fee, which over the life of a watch can quietly exceed what the watch cost.