The AppNexus iOS SDK by AppNexus allows developers to access and integrate the AppNexus API into their iOS applications built with Objective-C. This SDK was designed to work with the AppNexus Console and does not work with OAS.
Glympse, a service that allows GPS-enabled mobile phone users to temporarily share their location in real-time, has announced the availability of the Glympse platform allowing developers the ability to integrate real-time, temporary location sharing into third-party web and mobile applications. Glympse has also made available SDKs for iOS and Android as well as REST based APIs for use in websites and web based applications.
PubSubHubbub. Say that three times fast. If you're not familiar with PubSubHubbub, it's an extension of the RSS and Atom protocol that allows the feed to push content out when it's updated. That's just the sort of technology we should see from check-in APIs like Foursquare and Gowalla.