Unobstruct is one of the best content blockers for iOS. You can hide all kind of floating sharing bars and newsletters subscription pop ups which gives you a nice relaxing way to read a website. It's basically a pop up blocker fo the "modern" web.
You can also turn on Unobstruct in Safaris action sheet and hide floating crap manually. Great to remove annoying signup modals temporarily if you not registered on a particular social site with an f in its logo but stumbled into a link which goes there.