Why i don't have the effect Parallax in my iphone 4?

I install the iOS 7 beta 5 in my iphone 4, and i see, i don't have the effect parallax and i don't know why?

Added (1). And i'm not developer

Its hacked.

IOS 7 is only meant for developers. It is not a complete operating system so it still has a lot of holes in it. Unless you are trying develop something you should not even be trying to use it. You had to register as a developer before you could download it and the site does a great job explaining what it is capable of.

It's not safe at all to run iOS 7 when you're not a developer. Apple has been disabling unregistered devices running the beta. If you haven't already done so, you need to register your device's UDID with a developer account through a site like http://www.udid.in/.It's $5, and they literally registered my 4S instantly.