Update: Surprise! The app has been removed from the App Store.
The tethering setup process is similar (and just as tedious as past solutions), but as AppAdvice notes, the $0.99 app could be worth it for those who want to circumvent paying official Internet Tethering carrier fees.
Speeds depend on your actual iPhone’s carrier data connection.
Setup process (video) – Written info below
Results may vary, but we have independently verified with one iPhone that the app’s hidden tethering feature works. Apple will likely remove this app as soon as possible.