# Xcode 11.3.1 Release Notes Update your apps to use new features, and test your apps against API changes ## Overview Xcode 11.3.1 supports developing apps for iOS 13.3, iPadOS 13.3, tvOS 13.3, watchOS 6.1, and macOS Catalina 10.15.2. Xcode 11.3.1 supports on-device debugging for iOS 8 and later, tvOS 9 and later, and watchOS 2 and later. Xcode 11.3.1 requires a Mac running macOS Mojave 10.14.4 or later. ### General #### Known Issues - When you create an Objective-C category file by choosing File > New > File, the newly created file includes an import of the AppKit framework. This causes a compilation error for iOS, tvOS, and watchOS. (55977950) (FB7346800) **Workaround:** Remove the import of AppKit from the source file. ### Debugging #### Resolved Issues - Inspection of global variables in Swift and Objective-C works properly in `lldb`. (57884467) ### Interface Builder #### Resolved Issues - Fixed a crash that could occur when using an attributed string in a . (55737956, 57990674) - Fixed a crash that could occur after dragging a toolbar item out of the Allowed set in the canvas. (18133890, 57982132) ### Simulator #### Resolved Issues - Fixed an issue that would cause Xcode to time out waiting for Simulator.app to become ready, when multiple copies of Xcode are installed. (57050823, 57676897) - Resolved an issue that prevented Xcode from launching processes with Thread Sanitizer enabled on macOS Catalina 10.15.2. (57822138) ### Source Editor #### Resolved Issues - Fixed a crash that could occur when typing a doc comment after invoking undo. (56522994, 57762965) ### Swift #### Resolved Issues - Reduced the size of dependency files (`.d`) produced by the Swift compiler, which can improve incremental build times and disk usage for targets with many source files. (57361722, 57865813) --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)