The Google Shopping Content Objective-C Library by Google can access API data to sell products on Google, list ads, drive traffic, and increase sales. Developers can interact with the JSON API, working with iOS 3+ and Mac OS X 10.5+. Available introduction and example applications.
CallME's RESTful click-to-call API allows you to integrate Click-to-Call into your website as connect any phone number to another number easily. The service provides calling from a browser, voice messaging and a few other telephony features.