Use YOWATER, from developer Dave Walk, to track how much water you drink.

Try it

It’s a hack of the buzzy Yo, a mobile app that lets you message your friends, simply, “Yo.” The app got tech watchers in a tizzy when it raised $1.2 million.

You need to download Yo to use YOWATER.

Walk, a developer who works at health tech startup Grand Round Table, wrote about why he built the app here.

“I sometimes forget to drink as much water as I should and it’s annoying to input into another app,” Walk wrote. “With this app I’m esssentially using Yo as a button with which I can log something.”

Walk was previously the city of Philadelphia’s Civic Technology Engineer.