So there!
Definition 1 of 1
Pro Tip 1/3Triumphant Closure
It expresses a sense of victory or finality after making a point. 
I told you it would rain, and look at the weather now. So there!
Pro Tip 2/3Playful Mockery
Often used among friends or family in a light-hearted, teasing way. 
You said I couldn't bake, but everyone loved my cake. So there!
Pro Tip 3/3Childish Tone
Can sound juvenile, reminiscent of a child arguing or boasting. 
I got an A on my test, and you said I'd fail. So there!