I upgraded to a s7 from a iPhone. All my videos on Facebook are hd but I cannot view them in HD on my S7. I can view ads and trailers within the Facebook app in HD. The HD word is even there greyed out and I can click it to make it HD. I also have noticed some friends videos I can select HD. But everyone if my videos will not give the HD option. And they are indeed HD. I can use my wife's iPhone and select HD on them.