Meet the Pryme Vessyl: a smart hydration tracker with an app that provides you with real-time tips and notifications. It syncs with Fitbit, Jawbone Up, and other health trackers to better serve you. It takes into account your height, weight, age, sex, and other factors to measure your hydration level.
Pryme Vessyl has a light that gives you feedback. It comes with a Tritan shell and spill-resistant lid. Costs under $80 at this time.