This app was mentioned in 9 comments, with an average of 1.44 upvotes
Check out this app Perfect Screen Shot (Classic)
It also has a pro version Perfect Screenshot Ultra
You can easily decorate your screenshots with it, with some nice effects.
OP wants to show off he's using a Samsung? And doesn't know about Perfect Screenshot?
There is an app called Perfect Screen Shot which is actually the most popular app to do something like this.
I don't know about a website, but there is an app called Perfect Screen Shot