Normally people take to Yelp to recommend their favourite restaurants, slate the worst sandwich they’ve ever had or review the best places to stay nearby.
But apparently it’s also for some of the world's toughest prisons.
It appears inmates are writing reviews of prisons they’ve been locked up in, giving an astonishing insight into life in prison in the US.
Like this one reviewer who describes the tough conditions at Rikers Island Correctional Facility in New York.
User Jason “Captain Illicit” writes: “My first meal was Pasta and meat with no sauce, I was also given a milk, food tasted like wet noodles and grill gristle.
“I later learned to get a muslim halal card, and a jewish card, and know the kitchen staff to see which card would get me a better meal for the day.
“Chocolate pudding was great.
“When I would shower, I would take my clothes and wash them, people thought it was funny, but It was really a way for me not to get my own clothes robbed being there was no jump suits.
“The day room was controlled by the suicide watch, quality programming was usually spanish novellas.”
Elsewhere, users are also taking to Yelp to review Cook County Department of Corrections in Chicago.
One reviewer describes how inmates have to be tough to survive in an unforgiving and harsh prison environment.
User Frank G writes: “Keep to yourself, but remember this don't let anyone punk you. It is a sure sign of weakness and they'll move in.
“They're like dogs once they smell fear, they go crazy but, stand your ground and you won't run into many problems.”
Another man, Toby C describes how he has seen things “no man should ever see”.
He says: “Fellow inmates were extremely confrontational and would often degrade me based on racial, ethnic, and religious prejudices. Many seemed angry at fellow inmates for even looking them in the eyes. Would give it -10 stars if I could!”
Another man who says he's not a "low-life thug" but ended up behind bars after a fight, says: "The jail is a very dark place indeed."
And it’s not just prisoners who are taking to the site to review where they’ve stayed. Partners are describing visitation while even lawyers have taken to the site to offer advice to those visiting loved ones.
One woman takes to the site to describe what the conditions were like at Cook County Department of Corrections when visiting her ex who ended up in there, writing: “It seemed unsafe, even with prisoners behind bars, to wander around jail property.
"Take someone with you if you're visiting. Three stars for the automated system and low hassle on visitation."
User, Paul W who says he’s a lawyer writes advice about getting to and from Rikers Island.
He says: “Now, let me give you a quick piece of advice: I'm a lawyer, but this ain't lawyer stuff, it's common sense. DON'T BRING ILLEGAL STUFF IN WITH YOU TO RIKER'S. UNLESS YOU WOULD LIKE TO STAY A WHILE. SERIOUSLY.[sic]"
University of Michigan social justice scholar Reuben Miller told Tech Insider he thinks these Yelp reviews are part of a trend of “the public surveillance of criminal justice actors - similar to the way smartphones seem to constantly be capturing police officers using force on citizens”.
According to the site, Miller has spent years researching former inmates in Chicago and Detroit.
He told them the act of reviewing, while it may seem invasive is quite simply “the sharing of expertise.”
“There’s also families helping families. Here's what happened when my son was arrested. Psychologically it could be a way to voice frustration or gain some glimmer of hope out of an originally negative circumstance, to share in a relatively safe space that's valued by others."