First, Magisto launched a cloud-based video-editing platform for the web, which allowed users to upload their content and have it automatically stitched together into wonderful, watchable videos. Then it brought that capability to iOS and Android devices, which helped users make viewable content out of usually crappy mobile videos. But to use the Magisto platform, you had to download the Magisto app or go to the Magisto site. At least, until now. Magisto is opening up its API, which will allow third-party developers to be able to take advantage of its cloud-based video editing service in their own applications.