Apple today seeded the fourth beta of iOS 10 to developers for testing purposes, two weeks after seeding the third beta and almost two months after first unveiling the new operating system at its 2016 Worldwide Developers Conference.

The iOS 10 beta 4 update is available as an over-the-air download to those who installed the first three betas or the beta configuration profile and it's available for direct download through the Apple Developer Center.

iOS 10 is a major iOS update with ton of new features and design tweaks, including a new Lock screen experience with 3D Touch-enabled notifications, a more easily accessible camera, a redesigned Control Center, and a new widgets screen. According to Apple, iOS 10 is the company's biggest ever iOS update.

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The Messages app has been entirely overhauled with features that include background animations, bubble effects, Digital Touch, handwritten notes, Tapback replies, predictive emoji, and a dedicated App Store, and Photos has gained new facial and object recognition capabilities along with a Memories feature for rediscovering forgotten moments.

Over the beta testing period, Apple is tweaking the features introduced in iOS 10 to refine them ahead of the public release of the operating system. In iOS 10 beta 3, Apple introduced a new locking sound and haptic feedback when pressing the power button, an iOS 9 style Touch ID accessibility option, a new keyboard sound, an option to send Health data to Apple, and more. All of the new changes in iOS 10 beta 4 are available in our dedicated tidbits post and video.

iOS 10 is currently available to developers and public beta testers, with a full public release planned for the fall. For full details on iOS 10, make sure to check out our iOS 10 roundup.