"The information we collect includes unique identifiers, browser type and settings, device type and settings, operating system, mobile network information including carrier name and phone number, and application version number. If you're using an Android device with Google apps, your device periodically contacts Google servers to provide information about your device and connection to our services. This information includes things like your device type and carrier name, crash reports, which apps you've installed."
Google collects extensive device information including installed apps, unique identifiers, carrier name, phone number, and sensor data, with Android devices periodically sending this data automatically.