Total, not just glasses
Those figures include water from food, which supplies roughly a fifth of it. So the drinking part is lower than the headline number.
When you need more
Heat, exercise, illness and pregnancy all raise what you need.
Hitting it
Spread it over the day, keep a glass in sight, and log it in seconds. Life OS sets a target for you and lets you log water from the Watch, a widget or by voice.
Questions people ask
Is 8 glasses of water a day right?
It is a rough rule of thumb. Needs differ with body size, activity and climate.
Does coffee count toward water?
Yes, it contributes to fluid intake.