it works on simulator but the scrolling doesnt't work on the device

[surferbloggy]

Hi i've done an app and tested even on iphone 4s/5/ 6 in xcode 6 and it works on simulator
if i test on a iphone 4s device ios 7.1 and 8 the scrolling doesnt't work on any pages and there is a static page that seems covered and i can read the text and see the image it's very strange
i don't know what it is, i can't submit if it doesn't work on the devices
is it a cache problem ?
i delete the cache by deleting the app and the press home button and on button at the same time is there another way??
any suggestion to solve the problem : it works on the simulator but not on the device?? thank you for help