here it is (just copied from my facebook). system theme on ios like from PC. not a joke.

DOESN'T REQUIRE JAILBREAK !!!

compare both photos (sorry for bad quality but this theme isn't visible on screenshots and my phone's old):

1) ipad:

2) ubuntu PC:

i know that this compare here isn't perfect but: keyboard is themed, system is themed, some parts of websites also :/ (like bug then bug) and wallpaper (i made it by myself, available 3d-touch animated version, ipad and iphone - landscape and vertical)

for bug report - use apple's community because it looks differently on every device.

and info for developers - under mit license

=]