Apple has abused its dominant position by charging app developers an unfair 30% commission through its App Store, costing British consumers up to 1.5 billion pounds ($1.8 billion), a London tribunal heard on Monday.

Lawyers representing the class action said that Apple excluded potential rivals from competing for customers on devices running its iOS operating system by forcing developers to sell their apps exclusively through its own App Store and charging commissions of 30% for purchases.

Tech giant Apple is expected to face overcharging claims in Britain on Monday based on a complaint led by a King's College London academic who said the company is breaking competition laws.