Niantic unbans many Pokemon GO players, but not everyone is forgiven
Basically, all Pokemon GO accounts belonging to players who made use of bots, add-on map applications, or other third-party services that would allow them to hatch eggs without actually moving have been banned by developer Niantic.
According to the developers, “some players may not have realized that some add-on map apps do more than just show you nearby Pokemon.” This sounds like a decent reason to unban some of the players who weren't aware they are actually cheating when using these third-party apps.
The problem is these third-party apps hide their real purpose, so players have no way of knowing if they are doing something else in the background, other than allowing them to cheat. Apparently, many of these apps can be used as a collection tool by those who created them, thus invisibly collecting and forwarding data to a third-party without the knowledge of the user.
Niantic claims that by doing this, these apps can have an effect similar to DDoS attacks on its servers. That's why the company unleashed the banhammer on many accounts associated with using these add-on map tools.
source: Niantic
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