You get the Poke-radar app after you obtain the National Dex.
Nidorina: roue 211 (use pokeradar) Nidorino: route 221 (use pokeradar)
Use PokeRadar on Route 201
1. use a master ball. 2. use the poketch map app to track the Pokemon and weaken them then use any pokeball to catch them (this takes a while)
After you obtain the PokeRadar, go to Pal Park, which is at the end of Route 221. Professor Oak should be there, and give you the Chain App after talking to him.
You have to use the PokeRadar on Route 205
use your pokeradar at route 205 north
Use a pokeradar in route 211
go to sendoff spring and use pokeradar
Go to Valley Windworks and use the Pokeradar.
you have to use pokeradar in route 210. there is an 85% succession rate.
I think you can use a pokeradar, but if you can't, migration always works!
You'll find it in Fuego Ironworks, must use the Pokeradar.