Jonathan Zarra knew something about Pokémon Go that most people didn’t. As a beta tester this summer, the 28-year-old freelance developer had early access to the smash hit mobile game — and as a result, he could see that it offered users no way to chat with one another inside the app. And so Zarra built GoChat, an independent app that lets Pokémon Go users leave notes for each other at in-game locations.

"This is a feature that really should be there," Zarra says. "Especially in a location-based game — this just makes sense." Within five days, Zarra’s free app is approaching 1 million users and hitting servers with 600 requests per second. It may also drive Zarra bankrupt.

1 million users in five days

GoChat, which is available for iOS and Android, was released on July 4th — a day before Pokémon Go became available. Zarra posted about GoChat on Reddit, and the app was installed 10,000 times on its first day. As Pokémon Go grew into a global phenomenon, people began downloading GoChat at much higher rates. For the past two days, it’s been a top 10 search in the App Store. As of this writing, it’s the eighth-most-downloaded iOS social networking app. "The amount of traffic that we are currently getting has been the most insane thing ever, man," says Zarra, who lives in San Diego. "People are just blowing it the fuck up."

Also blowing up: GoChat’s servers. It was impossible to register a new account for most of the morning. And even if you did manage to log in, the app frequently crashes when you try to load a message. App analytics firm Sensor Tower estimates that 7.5 million people have downloaded Pokémon Go as of Monday, which would suggest that around 10 percent of all users downloaded a third-party chat app to go along with it.

GoChat is a hit, but it isn’t generating any revenue. Zarra resisted adding advertising to the app — "I hate ads," he says — and worries that attempting to monetize the app could draw unwanted legal attention from the Pokémon Company. He said he is currently having discussions with investors to keep the app solvent. Zarra declined to say how much he has spent on GoChat to date — "I don’t want people to know how stupid I am," he says.

"I don't want people to know how stupid I am."

Zarra hired a contractor using the firm Upwork to help build the iOS app and work on the database issues. "Trying to keep it up," Abdoelrhman Eaita, the contractor, told me in a Twitter message. "It’s really sad when you see your app crashing and you [feel] helpless about it." Eaita estimated that new servers to keep the app up would cost $4,000.

Aside from a few experiments, Zarra says, he had never built a mobile app before GoChat. He says he’s happy with the results — one user messaged him to say he had met a girl using the app and had made plans to take her on a date. And Zarra will figure out a way to stay afloat — eventually. "I’m going to be able to pay my rent," he says. "First and foremost, we really need to get our servers back online."

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