I think it would be annoying if it had what you were thinking because what if you saw someone you hated or someone relay hot 

It should have your name on it so if you forgot someones name than you could just look 

I wouldn't like having it because it would mean that people could look you up in the phone book

It would make me get beaten up a lot because I think a lot of bad stuff about people.

If it was real it would have age where we are from  gender relationship