Regulators allege that by requiring mobile phone manufacturers to pre-install Google Search and the Google Chrome browser, the U.S. company was denying consumers a wider choice.
Google announced two new phones Tuesday, the Nexus 6P and Nexus 5X, along with availability details about the newest version of Android, codenamed Marshmallow.
Android users said the company violated its own privacy policy by disclosing their names, email addresses and account locations to third parties without permission.
To boost sales of its phones and new operating system, Microsoft said it would provide tools to make it easier to design apps for Windows based on apps that run on Android or Apple.