“I would be lying if I didn’t admit that I have been in a real funk these last few days over this news,” writes Foursquare founder Dennis Crowley, speaking about the company’s plan to sunset the Foursquare City Guide app later this year in favor of focusing on its check-in app Swarm. The move reverses Foursquare’s ambitious 2014 decision to split up its app into two different properties: one for exploration and discovery and the other, Swarm, for sharing your location to find nearby friends. The...