Last May, the game has released a beta in U.S., and it appears to be turning Android and iOS users in selected other countries today. Initially, the app is limited in New Zealand and at the time of developing the app is not available in the UK and U.S., the two principal markets, but we can expect that will offered with this coming days.
Usually, this game uses smartphone, and you will experience Pokémon characters that can battle to real landmarks in cities. This game release is free to download but have some costs to unlock characters.
You can check this links for Android and iOS for more info.