Is Snap Chat Scandalous?

I have a female friend urging me to get Snap Chat but I haven't yet. Last I knew, Snap Chat was a scandalous app to have and I'm not trying to be scandalous. lol She says it's a fun way just to send cool stuff, I still don't quite have a good understanding of what it is? 

When did it go from being a 'controversial app' to being a cool way to keep up with friends? That is my biggest question and possible concern. If you have Snap Chat, what do you use it for and is it a good idea for me to get it?