So it turns out that Strava does some things. Some of those things may be useful and/or fun for you, some or many of them may not. So in that sense, it's like... pretty much anything, ever. I have also heard that Strava is heralding the End Times, ruining group rides far and wide, turning them into deadly hammerfests as everyone goes for every KOM with complete disregard for safety, good manners and proper comportment. I suppose this is possible, but I don't buy it and have not seen notable changes in group ride behavior from the time when Strava didn't exist to when it was just beginning to appear to when it exploded big time in 2011 or 2012. But I hear that I'm wrong about a lot of stuff, so who knows.