On Wednesday, European competition authorities unveiled charges against Alphabet Inc.'s Google subsidiary over its widely-used Android mobile operating system. According to the authorities, the strategies which enable Google to make money from its Android OS are anti-competitive.

The charges unveiled by European competition authorities against Google could potentially pose the biggest-ever challenge to the US tech giant's mobile strategy because they pertain to the company's Android platform.

If the charges stick, Google will apparently find it extremely difficult to increase its ad revenue, control costs, and reap profits from mobile devices in Europe.

The key issue which European competition authorities have raised against Google's Android OS is that the company's Android-centric contracts with smartphone manufacturers and wireless network operators require them to pre-load Google services - such as Google Search and the company's Chrome browser - on Android handsets which use the Google Play app store.

With the European authorities also highlighting the fact that financial incentives are offered by Google to its Android partners to ensure that they do not install rival search engines on their devices, Europe's competition chief Margrethe Vestager said that Android device manufacturers should not be limited by Google's 'all or nothing' deal; and added: "It is one of my priorities to allow consumers to enjoy a wide range of innovative platforms, products and services online."