A:AnswerThe Alpha glass will fit with the Otterbox Defender Case. However, you have to be extremely careful to get it exactly centered and every part of the glass pressed securely to the screen of the Galaxy S8. I found that even after doing this, the case can squeeze the glass off again at the edge, and you loose sensitivity. If I had to do it again, I would not get the Alpha glass and rely solely on the case for protection.
A:AnswerI have the otterbox defender for the s8.but the s9 has the same options.the case and the screen are sold separately.and due to the curved screen the glass they offer is probably not worth buying there is a huge loss of touch sensitivity.i have it and use it because I work in construction but it can be rather fruserating.unfortunitly there are no good screen protectors for the curved screens....i loved otter box on my s5 .the case is great but the screen protector is barely bearable.