i have a coating on my tounge that looks like thrash doctors have told me i hae!
Many "experts" will tell you, "Geographic tongue is a common tongue problem that normally responds to topical steroids" they often add "antifungal and antibacterial medications may be used for symptomatic cases and topical or systemic cortisone or prednisone may also be effective".
My mother had it, I have it, and my daughter has it. It is inherited. It is not dangerous or contagious. But when it flares up, I try to avoid acidic foods!! No worries, your tounge is just more interesting to look at in the mirror than most peoples!