More than a decade ago, I was covering tech out of New York when a hot New York–based app hit the scene. It was called Foursquare, and the idea behind it was pretty radical—it allowed people to “check in” to locations from their phones to let their friends know where they were. If you had the most check-ins in one location, you could even become the “mayor” of that spot.

Foursquare took the then-small group of New York techies—and their Bay Area counterparts—by storm. Fans were obsessed and—despite important privacy concerns—felt it was inevitably the future. Foursquare got a big stamp of approval when Andreessen Horowitz invested in the company in 2010, gushing about its “explosive” growth rate and huge market potential. “Foursquare is growing faster than Twitter did at this stage,” the firm wrote at the time.

It will not be news to you that while mobile location sharing went mainstream—and is alive and well today in all sorts of apps—Foursquare did not own that wave and become the multibillion-dollar tech platform its investors had in mind. 

To the company’s credit, it pivoted, merging with another location firm, and it now serves location data to marketers to help them understand customers’ in-store shopping behaviors. I suspect it’s a decent business.