Saying 'Bye' In English

Kate: I need to leave. It was great meeting you.
Or just,
I need to leave.
Or just,
It was great meeting you.

James: Same here.

Kate: Let's keep in touch.

James: Sure, why not.

Kate: Do you have my number?

James: Yes, I do.
Or
Can you please give it to me?

Kate: Okay, bye for now. See you later.

James: Bye, take care.