Today OnStar, a GM company focused on in-car communication and security, announced what it calls an API. Though not yet released, nor totally open and perhaps not even an API, the move is certainly part of "car as a platform." Building apps for cars is a movement that hasn't seen much progress since Ford's announcement two years ago. Though there is still a lot of potential, especially with the car culture in much of the US, some have questioned whether safety will stifle in-car apps.
Google has made several announcements including the launch of the Google Consumer Surveys API, the general availability of the Google Cloud Vision API with new features, the launch of Google Cloud CDN Beta, and the launch of Autodesk Maya. The APIs are available on the Google Cloud Platform site.