Apple is facing fresh legal heat from privacy company Proton, which wants to break open the iPhone's closed App Store.

We are seeking to permanently end anti-competitive behavior on the App Store, and we are joining this lawsuit to ensure that any future settlement enforces real changes to Apple’s practices and policies to benefit all consumers,

Privacy-focused software provider Proton has sued Apple over Apple Store policies, accusing the company of holding a monopoly on iPhone app distribution and forcing app developers to use its payment system with exorbitant commission.