A BSD-licensed single-header-single-source OAuth1 implementation. Usage is fully documented in the header. You will need to make your Xcode project link against CommonCrypto. Otherwise just drag and drop. Or better yet, use git submodules: git submodule add https://github.com/tweetdeck/TDOAuth Tested against Foursquare and Twitter. If you test it against something else, please fork and list the services you used it against here. Thanks. —Max Howell <max@tweetdeck.com>