The problem is simple. You're playing online and you come across a new friend but he's in Germany and he only speaks German. You as a native English speaker know no German...but he just helped you clear this really hard level & beat the hardest boss, and so you want to do more missions with him. How will you ever know what he's talking about or know how to respond back in something he understands?
As an online gamer you regularly play games with players from around the world, all speaking different languages. So how do you understand what your teammates or opponents are saying if YOU don't speak their language.
This is a problem I've face while playing online with people from Spain, Russia, etc, and is common for most online game players.
So I built a in-game translator app. You can launch the app without having to leave your game session to got into a browser. Then simply copy and paste the chat text, choose the languages, and hit translate.