Apple has released the second beta version of iOS and iPadOS 13.3 to registered developers

Update your apps to use new features, and test your apps against API changes.

Overview

The iOS & iPadOS 13.3 SDK provides support for developing apps for iPhone, iPad, and iPod touch devices running iOS & iPadOS 13.3. The SDK comes bundled with Xcode 11.2 available from the Mac App Store. For information on the compatibility requirements for Xcode 11.2, see Xcode 11.2 Release Notes.

Networking

New Features
Certain top-level domains (TLDs) such as .dev and .app are now in the Foundation URLSession and NSURLConnection HTTP Strict Transport Security (HSTS) preload list. An app which uses URLSession to visit a matching URL will always navigate to the URL as https://, and never as cleartext http://. See the HTTP Strict Transport Security (HSTS) Specification for more information about HSTS. (56247242)

Safari

New Features
Now supports NFC, USB, and Lightning FIDO2-compliant security keys in Safari, SFSafariViewController, and ASWebAuthenticationSession using the WebAuthn standard, on devices with the necessary hardware capabilities.

  Release Notes