On the page of any Sarahah user, you’ll find a simple prompt: “Leave a constructive message :)”. The flashing cursor, trapped in a text box, invites you to pour whatever thoughts you have about that person, good or bad, into an anonymous feed. Your deepest, realest thoughts, ready to be delivered, guilt free.

Sarahah, created in Saudi Arabia by Zain al-Abidin Tawfiq, has become a full-blown fad, taking over the feeds of Twitter and Facebook. The service, named for the Arabic word for “honesty,” quickly became a hit following its launch overseas in February, with BBC reporting more than 20 million users in a matter of weeks. Following its launch in June on the App Store, it rose to the top free app. Sarahah bills itself as a way to collect “honest” feedback — a chance for friends and co-workers to offer advice, comment on your strengths and weaknesses, or frankly point out problems.

On Facebook and Twitter, you can spot a Sarahah user through screenshots of the teal speech bubbles that hold their anonymous messages. The hashtag for the service is a cascade of comments in a variety of languages. You can’t reply to anyone on Sarahah, so some users choose to respond to their commenters this way. Searching through the Sarahah hashtag is a mix of people earnestly soliciting feedback, sharing their responses, or verbally rolling their eyes at the service. Much like posting a selfie, there’s a certain performative nature to it. People have taken to posting their compliments online as a sort of celebration.

For users who’ve decided to take the plunge, their interest is a combination feedback and general curiosity. I spoke with more than a dozen people who’ve used the app, whether to invite observations, comment, or both. User David Jenkins told me the experience for him has been eye-opening. “I personally get a few wake-up calls, I suppose,” he says.

“I figured I would get a few anonymous buttholes or whatever. But mostly I've been getting people coming out of the woodwork saying how much they miss me. Or how I wish I had kept in contact with them.”

Twitter user Steven Coffin told me that, although he didn’t have an account, he’s sent comments to people he follows online. He says he prefers to send people compliments. “I like making people happy,” he says. “I know a lot of people have stressful days or just horrible days and I want to make their day brighter and Sarahah gives me an easy way to do that.”

He continues, “Also, being anonymous stops them from thinking, ‘Oh they are just saying this because they are my friend,’ so I like that I can make people happy and that it doesn't matter who gives them the compliment, the only thing that matters is the compliment itself.”

The users I spoke with have a surprisingly sunny view of how the system works, with many of them emphasizing their desire to brighten people’s days with kind words. In testing out Sarahah myself, I was surprised by how overwhelmingly positive the comments I received were. (Less a humble brag as it is an honest declaration of shock.) One user told me that the anonymous nature of the platform impacts their desire to comment more, rather than the nature of comments. “Being able to throw a joke out there without having to have my name attached makes me more willing to make them in the first place,” they said. “And I think the gratification of it actually being successful isn’t diminished much by the anonymity, you still accomplish the goal of making people laugh.”

Another user told me it makes it easier to approach people they’d otherwise not feel comfortable talking to. “I mainly just try and send something encouraging to brighten their day cause I figure we could all use that,” they told me via DM.

“I don't really get much of anything out of sending the comment, but it only takes a short amount of time and I hope it brightens up their day so why not?”