Best way to handle internet authentication pages within iOS app?

Best way to handle internet authentication pages within iOS app?

What is the best way to handle WIFI authentication pages within an iOS app
(often found in free WIFI zones, hotels, etc.) such as within Settings.app
(displays a web view within a modal when user needs to be authenticated)?
I have some ideas for a custom solution such as checking for redirects,
content types, and then displaying a web view to the user, but wondering
if there is an already implemented pre-existing solution.
Background:
iOS 5+ supported
All network requests routed through AFNetworking