Will there be any harm to me if somebody uses my Publisher API key without my knowledge ? I mean somebody knows my API key and he is using it without informing me, how will it affect my account ?
Yes, Kite Publisher is free. It could be a difficult task since it can be used by anyone and not bound to one user. I would suggest just deleting current app and creating a new one.
Can I track who is using my API key ?
I heard on some Youtube video that Publisher API key is free, is it true ?