I know that feel. I've never wanted to slam my phone to the ground more.

You know you suck when you fail to catch a Magikarp.

A friend of mine once said:

That's why Splash is the best move in the whole Pokemon-verse.

I have no idea how a Magikarp can dodge like that. But that last panel expression is the best example of my response.

Duh, you have to weaken it first.
So, grab it by it's tail fin and smack it a few times onto the ground.
That should do the trick.