You can customize quite a few things if you've jailbroken your iPhone, iPad or iPod Touch, one of them is the boot logo.
For example: if don’t like the Greenpois0n animated boot logo after jailbreaking your iOS device using Greenpois0n and want the Apple boot logo then here is a simple way to change it thanks to the BootLogo Addon available in Cydia.
* Launch Cydia from your jailbroken iOS device’s home screen.
* Then tap on the Sections Tab.
* Tap on Addons (BootLogo) from the list.