The Android kernel contains not only the software layer that bridges the gap between hardware and apps, it also includes various drivers and code beyond that which most would typically consider part of the kernel.
End users don’t directly benefit from this type of release but developers do — professional and hobbyists alike. Seeing how a company accomplishes various things programmatically not only can make other apps better, it can also help identify bugs which can be fixed in future updates. Developers can also build hooks into various unpublished APIs, build similar code into their projects, or even accelerate the development of custom ROMs.
If you’re interested in seeing what makes your Inspire 4G tick, download the source and check it out!
Source: HTC Developer Center