A:AnswerMy phone is 6.25" diagonal and it fits pretty snugly. A 5.5" diagonal phone would probably work but be a little loose. I would recommend that you try one in a store. I'm guessing it would fit a 6" diagonal perfectly.
A:AnswerProbably will work. I've had the Galaxy phones and just bought a 7 and it fits nicely even with the back cover on. It's a little shy of 6 x 3 but the case will stretch a bit.