Apple is preparing to unveil a slew of homegrown apps as part of its Worldwide Developers Conference, a global gathering of app developers that will see it tease its latest iOS software.

The iPhone giant's annual gathering will see 5,000 developers gather on Monday in San Jose to hear the latest updates to Apple's iOS 13 software.

But this year's conference comes as the California giant faces a wave of pressure on its apps business and a growing conflict with developers it has courted for over a decade.

The headline launches are expected to include an iPhone dark mode to make the screen easier on the eyes, according to 9to5Mac, and updated versions of apps including Mail, Reminders, Books and updates to its Safari browser and Files storage app. Its iMessage app will also add new headshots to make it appear more like a rival to WhatsApp.

Apple will also reveal new updates to macOS and watchOS, its software systems for MacBooks and Apple Watch devices. MacBook users can expect to see more iOS apps getting versions that work on their laptops, while the Apple Watch will be given its own App Store and a version of Books for podcasts.