It could just be a normal coating on the back or it could be a variety of different things like bacterial growth or infection.
I have the exact same thing except the thin white stays in the back of tongue for me. My friend has it to. Everyone says its very common for women but I don't believe it. I also have fissures going down the middle of my tongue. They aren't deep though. I would like to know what it is.
plz everyone if u can e-mail me at ***@****