So as you may know, Pokémon Go has been released in the USA, Australia and New Zealand. However it is possible to get the game regardless, all you have to do is to follow these links (I'm not certain if this counts as advertising but this is the simplest way to download the game)
How to download Pokémon Go for Android
How to download Pokémon Go for iPhone
How to download Pokémon Go for Android
How to download Pokémon Go for iPhone