My question is, does it just need this to install, and then the space currently occupied by iOS will free up, or will it use that space PLUS an additional 3.1 GB?
My phone is only 16 GB and I already have trouble getting everything I need to fit on it, so I'm not going to download this update if it's going to occupy that much ADDITIONAL space.
I can't remember if the last software update I downloaded required additional space or not. I don't think I paid attention at that point.
Basically, here's my question summed up:
My phone is running on iOS 6. This is occupying x GB of hard drive space. The new iOS 7 download requires 3.1 GB. When the new download is finished, will the original x GB become freed up or will it be taken over by iOS 7?