PokeDetector

PokeDetector is a Pokémon GO companion app that automatically detects nearby pokemon. After you log into your account (or any account, really) the app vibrates every time you get close to a pokémon. This feature actually works especially well on a smartwatch.

It's important to keep in mind that PokeDetector will notify you whenever a pokémon is nearby. It doesn’t matter if the pokémon is rare or common, or if you already have that particular one or not. If you want you can set a filter in the options so you only receive notifications when a pokémon on your particular list gets detected. This is a paid feature, however.

PokeDetector is an interesting app for people who play Pokémon GO regularly. Thanks to this tool you don't have to have the game open all day (which consumes loads of battery).