Pokémon will be coming to smartphones real soon on iOS and Android devices as a Pokéland app. You will be able to take your Pocket Monsters out for a field day on various islands and stages where you can battle it out. All that you will need is your smartphone, an internet connection and your Nintendo Account.
The Android alpha test is currently being performed in Japan at this moment, but no further news has been released as to when this app can be expected and when it will be available internationally. What is known is that it will feature 6 islands, 52 stages, and 134 different Pocket Monsters. Alpha testers will also be able to progress to the 15th floor in the Champion Tower.
The Alpha test will run until 9 June 2017, after which all data will be reset for the official release.
Source: Kotaku
