"Google, Facebook, Microsoft, and Twitter joined to announce a new standards initiative called the Data Transfer Project, designed as a new way to move data between platforms. In a blog post, Google described the project as letting users “transfer data directly from one service to another, without needing to download and re-upload it.”
The current version of the system supports data transfer for photos, mail, contacts, calendars, and tasks, drawing from publicly available APIs from Google, Microsoft, Twitter, Flickr, Instagram, Remember the Milk, and SmugMug.
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The existing code for the project is available open-source on GitHub, along with a white paper describing its scope. Much of the codebase consists of “adapters” that can translate proprietary APIs into an interoperable transfer, making Instagram data workable for Flickr and vice versa."