With the Google Custom Search iOS SDK by Google, users have access to the JSON API considering development in Apple devices. References include example applications, source, and service folder. AdSense, Calendar, and Cloud Storage are additional Google APIs that benefit from this library
Microsoft is one of the first--and certainly the largest of--customers of Wolfram Alpha's commercial API (our Wolfram|Alpha API profile). For math and nutritional searches, Microsoft's Bing now uses Wolfram results.
When we wrote about APIs fueling an "instant" frenzy, there were only four mashups in our directory tagged instant. We've added more than that just this week, taking our total to 16 instant mashups. But the most common type of instant mashup may surprise you.
Bing has announced that it will move the company’s Content Submission API out of private beta and into a public beta launch that will significantly expand the number of developers working with the tool. This API helps publishers and site owners ensure that their new content is properly indexed.