The banning of Pokemon GO [Free] mappers and tracking services has given the game's community some consternation. Particularly considering that in-game tracking is seen as poor, and has gotten worse since launch. Niantic has released a statement discussing some of their thinking behind why they've been issuing bans and shutting down access to third-party services:
Some players may not have realized that some add-on map apps do more than just show you nearby Pokémon. Each end-user app can be used as a collection tool by the app creator, invisibly collecting and forwarding data to the app creator with or without the knowledge of the end user. These apps can have an effect similar to DDoS attacks on our servers. Additionally, Niantic says that while some account bans for being associated with trackers are being lifted, continued use of unauthorized services may result in bans in the future. So, if you decide to use a mapping service of some sort, be careful. Hey, at least that Ingress [Free] intel map is still live, and perhaps Niantic needs to launch something similar for Pokemon GO.

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