Today we're proud to announce the first internal application project to be open sourced for community. As of today the code for the Sailfish Browser can be found in GitHub version control system at http://github.com/sailfishos/sailfish-browser

The Sailfish browser has been built on top of Mozilla open source Gecko browser engine, using EmbedLite embedding API (also known as IPCLiteAPI). Our objective is to make this the first step to get official support from Mozilla Corp. to a mobile browser based on Gecko and embedded in Qt.

Read more here https://lists.sailfishos.org/pipermail/devel/2014-February/003352.html