(May 21): Apple Inc Chief Executive Tim Cook on Friday told a court that threats to iPhone security and privacy required tight control of the App Store, which "Fortnite" game maker Epic Games says is a monopoly that Apple illegally abuses.

The testimony constitutes Cook's most extensive public remarks on the App Store, which anchors Apple's US$53.8 billion services business, at a time when the company that once urged the world to 'think different' is criticized as too big and too powerful.