. Freebase Apps is the hosted application environment that lets Freebase users create applications that query the Freebase open data entity graph in various ways. Google has announced
that the Acre platform that powers Freebase Apps is being open sourced.
Last month Google acquired MetaWeb, the company that developed Freebase. Google's plan was to take their open data graph and make it "even more open." Freebase is licensed under the Creative Commons and contains about 12 million real-world entities such as people, places, films, events, books, businesses, and much more. The graph database has about 400 million facts and connections between entities. All of these are accessible through a REST API.
Until now, Acre development has been tied to Freebase.com, forcing you to develop Acre apps on Google servers. Google says they've made Acre work with source code that's stored outside of Freebase. You can run Acre on your own machines and in your own development environments, allowing you to develop standalone, non-Freebase apps using Acre. This helps developers avoid the resource limitations in Google's shared environment. However, Acre still has some close ties to Freebase, such as API hooks for quickly making Freebase queries.
You can download Acre here
and try it out.