The main point is that Google is denying the consumers a wider choice of mobile apps and services and thereby standing in the way of innovation by other players.
That is illegal in the EU.
These are the alleged violations of the antitrust rules:
Requiring manufacturers to preinstall Google Search and Google's Chrome browser and requiring them to set Google Search as default search service on their devices, as a condition to license certain Google proprietary apps;
Preventing manufacturers from selling smart mobile devices running on competing operating systems based on Android open source code; and
Giving financial incentives to manufacturers and mobile network operators on condition that they exclusively preinstall Google Search on their devices.
Google's business practices may lead to a further consolidation of the company's dominant position in general Internet search services, the commission noted.
Those practices may affect the ability of other mobile browsers to compete with Google Chrome. They hinder the development of operating systems based on Android open source code and the opportunities they would offer for the development of new apps and services, the commission said.
The complaints have come from Googles competitors with Nokia (Microsoft) and Oracle as the front runners.
Similar investigations by the US Federal Trade Commission can not be ruled out.
Google claims that suing them will only do harm to consumers and innovation.
Senior analyst at the IT & Innovation Foundation Daniel Castro put it like this:
This would create a risk, that tech companies would design products to meet arcane competition regulations rather than consumer needs.
This might be seen as another fight in the IT wars that have been going on for some time.
John M Simpson the director of Consumer Watchdog said it like this:
This is the same kind of thing that Microsoft did when it bundled its browser in with its operating system
While Google makes Android freely available, it's got strings that come with it that unfairly favor Google's apps if you're going to use the Android software
So far Apple seems to be flying under the EC radar.