PokemonGO is the summer's new emerging fad among kids and older kids/twenty-somethings. They're all walking around town trying to catch the Pikachu of their dreams. If it were that simple, we would have had something like PokemonGO for everything we do, right? Like food and google maps!
The game has Pokemon battle functions there also so some willing trainers may want to fight. If you both agree to a duel, you match your Pokemon with theirs to grow their stats, if you win. The battles can happen anywhere the two players are so they're added to the game's interface capability. Even if you don't battle just playing adds to the PokemonGO system.
It kind of makes us wonder, will Pokemon come out with a DS game with better and more things to do. It would already have been geocached to myriads of millions of places and tech. So play as much PokemonGO as you want and you'll become a Pokemon master before Christmas!