How is Snapchat still on the App Store?

Today for the first time I decided to read up on Snapchat after seeing the Verge article that said FB offered $3B for acquiring the company. I had heard of the name before but had never tired to understand what the app did exactly as I wasn't interested.

After some research I've come to the conclusion that Snapchat is nothing but a glorified t** pic for d*** pic noods service.

I thought Apple was against such pornographic, sex services related apps? They can't be oblivious to how people are using this app now, can they?