Hiding purchased apps doesn't work.
i Have IOS 8.4 on my iPad. When I tried to swipe left and hide, they all came back when I reopened???
There is a bug if you try to hide them directly on your iPad, you need to use your computer's iTunes : Hide and unhide purchases in iTunes or iBooks on your Mac or PC - Apple Support (there is also a bug affecting hiding apps on a computer's iTunes, when you hover your mouse pointer over an app in the Purchased section the 'x' might not show on its top left corner, but clicking on that corner should still hide the app).