How it works
Why a screenless wristband lasts 45 days on one charge
Why a smartwatch needs charging daily but a screenless band lasts 45 days: what drains it, how Bluetooth saves power and why the phone does the maths.
sleep
How your band guesses whether you're in deep sleep or REM
Without seeing your brain, a band slices the night into 30-second chunks and guesses your sleep stage from pulse, HRV and movement. Here's how it works.
artificial intelligence
We didn't discover mathematics. We are mathematics
Not even its creators fully understand how AI reasons. That raises a bigger question: what if we ourselves are mathematics discovering itself?
Sleep
What time Spain falls asleep: data from 36,700 real nights
Spain falls asleep at 00:30, an hour later than Germany. Data from 36,700 nights in five countries, ahead of the 25 October clock change.
sensors
Pulse with light: how a wristband reads your heart from outside
How a wristband knows your pulse using only light: what photoplethysmography (PPG) is, how it works out pulse, HRV and SpO2, and why it sometimes errs.