A mobile app created by Niantic, Inc. and the Pokemon Company. Players take their smartphones with them, walk around, and catch Pokemon, just like in the main series. The game initially included Generation I Pokemon, but began adding Generation II Pokemon in early 2017 and Generation III during the same year's Halloween event.
The game is often set as an example of a "flavor of the month" fad. Its online popularity dropped drastically a few months after its release; many blame this on the lack of updates and content on launch, Niantic, Inc.'s poor management and playerbase communication, and its freemium pay-to-win system prevalent in many other mobile games. However, despite the decrease in internet activity, it's still a popular game, and some cite the game and the release of Pokemon Sun and Moon as the causes of a resurgence in franchise popularity overall. More features being added over the course of 2017 have also drawn back some of the initial fans that dropped off for the above reasons.
