How to hide Photos from iOS The new OS X Photos App allows to hide photos. Hidden photos will only appear in the Hidden album (or in any album which you explicitly added them to).

However, the Hidden photos keep showing on the iOS Photos App. iOS detects they are hidden, but it merely hides them from the image picker controller on third party apps. They can still be viewed in the main Photos App on the All Photos section. Is there any way to hide them from All Photos as well?
No. Hiding photos on iOS prevents them from displaying in Moments, Collections, and Years, but they will continue to show in any of the albums under "Albums". 

Unfortunately, short of deleting them and then restoring them within 30 days, you are limited to the provision that Apple developed.