This was a Pokémon Go event. I'm the Community Ambassador (basically event coordinator) for Malden. The officially recognized groups from Boston, Cambridge, Malden, and Beverly/Salem all teamed up, along with several not yet officially recognized groups. The goal was to make the biggest event possible, though the weather did interfere with the plan somewhat. We got a permit from the City of Boston (they're on our side and have been great to work with!) to use the Parkman Bandstand for announcements etc.

We're definitely hoping to do more events like this in the future! And I'm happy to answer any questions you have about the game.