Last Summer, Apple unveiled the latest version of its mobile operating system, iOS 5. The update contained more than 200 new features including iMessage, iCloud, and a revamped Notification Center.

Apple released the software last October for the iPhone 3GS, and all newer devices. So what do you do if you own a first or second generation iPhone or iPod touch and want to install iOS 5? Enter Whited00r…

The folks of the Whited00r community have been remanufacturing Apple’s mobile software for a couple of years now. You may recall them bringing iOS 4 and its multitasking feature to the iPhone 3G and other non-supported devices last year.

Now the team is back with a customized version of iOS 5. Installing it is as easy as downloading the firmware from the Whited00r website, and running iTunes. But before you get started, there are a few things you should know.

First of all, the custom firmware is missing some of iOS 5’s biggest features, including Notification Center and the App Store (yeah, no App Store). And its iCloud component is really just a front-end for a redesigned DropBox-sync feature.

But on the plus side, it does contain several iOS 5 features. And the ever-important multitasking and custom wallpapers are there. It even includes a host of pre-installed jailbreak tweaks and of course, the Cydia Store.

Unfortunately we don’t have an older device to confirm if Whited00r works as advertised or not, but initial feedback seems to be rather positive. For those of you interested in trying it out, you can find the custom firmware and a brief tutorial on how to install it here.

Have you tried Whited00r 5.1 out yet? What do you think?