Pingomon

Pingomon is a companion app for Pokémon GO that helps you find more Pokémon.

See an interesting Pokémon? Let people around you know! Want to find more or better Pokémon? Pingomon is here to help! Pinging a Pokémon broadcasts its location to other users in the local area, so you can find what you want, even when you're not playing.

Filter incoming pings by distance or species to help find exactly what you want (nobody needs Pidgey notifications, right?).

Unlike other Pokémon locator apps, this does not violate the terms of service by using Niantic's server for locations, so you don't have to worry about your account being banned for using it. It relies on people sharing, so the more local people you get using it, the better it will work.

-- Pingomon is not affiliated with Niantic, Nintendo, or Game Freak in any way. I'm just a guy who thought it would be useful.