Google has denied the way it handles its Android mobile operating system is anti-competitive.
In 2015, the European Commission said it would investigate whether Google "abused its dominant position" and "hindered the development" of rivals.
Google argued Android was a "flexible" platform that had "expanded competition" rather than hurting it.
The European Commission told the BBC it would carefully consider Google's response before making a decision.
Reducing costs
The Android operating system is open source, with a majority of the code available for device manufacturers to take, modify and use for free.
Companies are free to take the code and develop it into their own operating system - shopping giant Amazon has done so with its Fire OS.
However, manufacturers must negotiate with Google if they wish to add Google Mobile Services (GMS), which include the popular Google Play app store, Chrome web browser and Google Search app.
