Is there a way to downgrade to iOS 6.1.3.?

Question

Good evening!
Yesterday I made the worst choice of my life: I updated my Phone 4S to iOS 7 and I'm having lots of problems.
My problems with this version is that its graphics are too white and they are making me literally sick! I'm having headaches, nauseas and my eyes are perpetually burning because of that operative system!
I have always dreamt to have an iPhone and last year I finally managed to get it and I paid a big amount of money for it: after the upgrade I really thinking about selling it and revert to a normal phone. I filled a form of complaints in the feedback available on the website, I hope to get an official answer.
I want to know if anybody knows a way to go back to iOS 6.1.3.!
Thanks!

Answer 1

You wil not get a response to any feedback you submit to Apple, just so you know. Regarding the iPhone, potentially useful ideas, quoted from pvonk, another user here:
General -> Accessibility -> Bold Text to ON. You may still have to squint a bit but letters will be ~much~ easier on the eyes.
General -> Accessibility -> Increase Contrast to ON. This takes away the bright fuzzy backgrounds when you open folders and makes them less fuzzy grey ones. It also darkens the bright fuzzy bar across the bottom of the screen to be a darker grey. It does not darken the bright fuzzy folders icons on the app pages or make Notes, Reminders or new Safari pages (or existing ones while you type a new address) much better, but is a huge step forward. It definitely makes mail and Messages much less pain-inducing, though they could stand to go darker.
General -> Accessibility -> Reduce Motion to ON. This seems to cost me the pretty effects with app icons, but with all of the fuzziness they've added to folders and the your-apps bar, it helps avoid ~shifting~ fuzziness. Which turns out to cause problems for me. Who knew?
General -> Accessibility -> Invert Colors to ON. ******* ONLY while in the Settings menu or Apple's screens like Safari, Reminders and Mail. I've been told I might be able to assign it to a triple tap, which should make switching easier. Haven't figured out how yet.
App Switcher - Either don't use it or kill all Apple screens you aren't actively using. This cuts down on the large light squares that fill the screen in the app switcher now. Not using it would be a hassle, but would also cut down on the heightened visibility of everything I have open when switching between apps I use at work. I'm undecided which I'll end up going with.
Use new screen pages instead of folders. I love the new folder design. My migraine-ridden brain doesn't, though. /-: With the old folder design, you knew an app in a folder was on screen if the folder was open and could let your gaze sweep over it multiple times to identify the icon. Now it may not be on the screen, so you have to focus specifically on smaller icons against a fuzzy-ish background. Focusing on something meant to be fuzzy is apparently one of my headache triggers. If the folders were darker or I could show the same number of icons, this would be much less a problem, but for now... I'm not sure that having a page for each folder is doable or worth the hassle, though. Might just end up moving the apps I use less often into a set of folders on a last page I don't have to visit often or just deleting them to minimize folders.
Remember your brightness setting needs to be lower than it looks. This one seems obvious but surprised me with the frustration it causes. When you open the lower dock that has the brightness control, it darkens the rest of the screen. If you set your brightness so that what you want to look at seems right, it will brighten further after you close the menu and go back to it. I don't have a feel yet for how much lower I need to set the brightness, but I assume that will come with time. Also: Setting brightness higher makes the menu itself brighter to look at, so judge headache likeliness with that in mind.
Settings -> Wallpapers & Brightness -> Auto-Brightness to OFF. This OS is super on-the-ball about adjusting brightness automatically. Which is awesome sometimes, but less so when you manually set the brightness, go back to the screen and watch it change from what you just set it to. You may end up with darker screens than you want until you adjust the setting, but you won't end up with brighter screens than you want.
Some additional tips here:
http://tidbits.com/article/14122?rss&utm_source=feedburner&utm_medium=feed&utm_c ampaign=Feed%3A+tidbits_main+%28TidBITS%3A+Mac+News+for+the+Rest+of+Us%29
Regards.