it check how close you are with your Pokemon.
it is needed for:
-some Pokemon need love to evolve. There you can check how long till evolution.
-an old lady somewhere in the game can teach you dragon types Draco-meteor!It depends on how much love you give them.
Chat with our AI personalities
The friendship app or frenship checker is given to you by a girl on the first floor of the Eterna city Pokemon center.
You can find the app in the Pokemon Center in Eterna City. Talk to one of the girls.
In Pokemon Diamond the Friendship Checker (also called the Happiness Checker) app is #6.
In Eterna City's Pokemon center. Talk to a woman in there and she will give you the poketch app- freindship checker.
Fly/walk to Eterna City and go into the Pokemon center. Talk to the girl inside there and she will give you the friendship checker.