I'm using this one. It works pretty well for running.
https://www.amazon.com/gp/aw/d/B013D2GDTS/ref=mp_s_a_1_2?qid=1442373626&sr=8-2&pi=SY200_QL40&keywords=note+5+armband&dpPl=1&dpID=51xcsG4K%2BSL&ref=plSrch