US internet giant Google has rejected EU allegations that it abused its market dominance of its hugely successful Android mobile phone operating system.
"Android hasn't hurt competition, it's expanded it," said Kent Walker, senior vice president and general counsel of Google, said in a blog.
Google was responding to a long list of charges involving Android that the EU filed in April.
They include the claim that the firm used practices such as making manufacturers pre-install its market-leading search engine as the default in phones.
"The response we filed today shows how the Android ecosytem carefully balances the interests of users, developers, hardware makers and mobile operators," the blog said.
Google's response comes a week after the company rejected separate EU charges over online shopping and over its advertising services.
The Android charges are seen as especially sensitive to one of Google's most strategic businesses that could alter a global smartphone sector which is fast taking over traditional PC's as the biggest segment in the world of computing.
The EU in its charge sheet accused Google of obstructing innovation by giving unfair prominence to its own apps, especially its search engine, in deals with mobile manufacturers such as Samsung or Huawei.
"No manufacturer is obliged to preload any Google apps on an Android phone," Google insisted.
Google is also accused of restricting manufacturers from installing rival versions of Android, an open source software operating system, on their phones.