This is a question I’ve been asking myself. The game its pretty simple, you go and catch “Pokémon” through “Pokéballs”, after you have a team that can fight gyms after you defeat it put a team in the gym so it can defend it. Then you get eggs from the “Pokéstops” with “Pokémons” inside that hatch with distance, it doesn’t say into what it will hatch its pretty random, so you can expect rare “Pokémon” with longer the distance. Same stuff you see in past games with different ways of doing it.
Ok so it’s basically “Pokémon” for iPhone, then why is everyone playing it, is supposed to be a game targeted for younger audiences, not for the creepy old guy inside of their car trying to defeat the nearest gym on midnight or for the candidate for president shouting her team on Twitter. Well, the answer is very simple, the game is fun not like the ones for portable consoles but still fun. It’s fulfilling catching a “Zubat” on the first try, it’s fun to walk while you catch and hatch, the battles are easy but enjoyable, joining a team you represent makes you feel like a grunt from team rocket, the monsters are pretty unique (except for “Goldeen” who is a fish with horn).
Still, I appreciate more the games than the app because the battles have more substance and feel more planned and it isn´t manipulative like the app making you travel to bodies of water with aquatic “Pokémon”, not that fun for me. If you have a lot internet and free time go catch ‘em all.