From firing off angry tweets to writing nasty Yelp reviews, there are many ways to vent about bad customer service in the age of social media.

But while it feels good to blow off steam, it doesn’t always produce results for companies or customers.

Tello, a year-old mobile app that lets consumers rate the employees who served them at restaurants, shops and other businesses, is looking to make all that online griping more productive for both consumers and businesses.

On Wednesday, Tello debuted a customer feedback service with an online tool that lets businesses respond directly to the customers who rated their employees. A manager at a restaurant can then reach out to a disgruntled customer to ask for another chance. But it’s not all bad–a retailer can inform a customer that the pair of shoes they wanted are now in stock and a business can also write back to thank a customer who gave an employee a stellar review.

The service also lets businesses track the ratings that their various employees are getting on Tello.