Apple is facing the biggest lawsuit in the UK, with more than 1,500 developers seeking up to $1 billion in compensation.
It is alleged to have abused its dominant power by charging 'anti-competitive' fees or commissions of around 15% to 30% on sales in applications made through the iOS App Store.
Developers argue that unfair fees prevent them from raising funds that could be used for innovation and app development.
The claim at the Competition Appeal Tribunal was led by Sean Ennis, a professor at the Center for Competition Policy at the University of East Anglia and a former economist at the OECD on behalf of 1,566 app developers.
He said in a statement that Apple's charges were excessive and that it had the power to do so due to its monopoly over the distribution of applications to iPhones and iPads.
In this claim, all UK-based developers are automatically included unless they opt out.
If successful, the damages awarded will vary based on each developer's iOS app business, potentially reaching millions of dollars.
