How to download GB4ios on IPhone 5c iOS 8.1?

So I tried downloading the 2.1 version and the window that said "install" came up. I clicked that, it began downloading, but then another window popped up saying it could not be downloaded at this time. What do I do? No jailbreak

Set your date back to before febuary 2012. That's what I had to do for my iPhone 5, and it's not jailbroken. It says that on the website, I think. Hope that helped!