HOUSTON - On Thursday, the head of Nextdoor, a website and app that helped organize boat rescues and save lives during Harvey, was in Houston to say thank you to law enforcement officers and other “heroes” of the storm.

Nextdoor allowed both residents and first responders to get news on what was happening in each specific neighborhood around the Houston area.

It was one of many social media platforms and apps that rescuers used, from well-known ones like Facebook and Twitter to others like the walkie-talkie app, Zello.

Nextdoor’s website and app are usually where neighbors do things like seek out recommendations for a babysitter, sell items, or report suspicious activity.

However, during Harvey, tens of thousands of new users signed up, and the app had a more than 500 percent increase in posts, replies, and alerts.

Users also sent out more than 3,000 urgent alerts per day, compared to a dozen on a typical day.

“It became really clear early on that one of the things that matters that when you have extreme events like Harvey, like a storm, it’s natural for people to come together and help each other,” said Sarah Leery, Co-Founder of Nextdoor. “We are humbled and proud to see that people have turned to Nextdoor and really look to their neighbors to help and that their neighbors were there to respond and help them in a time of need.”

Leery says in the six years since she launched the site, Nextdoor now covers more than 85 percent of Houston-area neighborhoods. She says about one out of every five area households uses the app.

Leery also said she and her employees have been blown away with the way the Houston region has come together during and after Harvey.

She says the whole country is supporting the area and sending a lot of good thoughts and prayers during the recovery process.