For those that really want to quantify everything they drink, check out Vessyl.
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We started developing The Hug because we wanted to change our hydration habits. The Hug coaches you towards balanced hydration by showing you relevant data, feedback and giving prompts. Thirst as a reflex does work well for a lot of people, but for the ones it doesn't (like me), The Hug is a useful device. By the way, Vessyl is an awesome product I think! Targeted especially to those who tend to gulp down too many calories....
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There is already a tried and tested way of checking how hydrated you are.
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