The ideal word, which can be either an adjective or a noun, should describe (or at least allude to) the idea that doing something anywhere and anytime with anyone, or that something is done anywhere, anytime, by anyone.
If no such word exists to satisfy all three above, then a word to satisfy the former two (anywhere and anytime) is OK too.
Update: I agree that some context should be given to better narrow down the choices. I mainly want to describe something (e.g. a service or goods) that would enable people to complete a task or to accomplish some goal anytime and anywhere.