Updated way to define text macros using a plist file.

• Define text macros for a user, a project, or a specific user in a project.

• Customize the new file header. For more information, see Customizing file headers in Xcode Help.

Updated the indexing engine to include the ability to index files as they are compiled.

Split the Devices window into separate panes for devices and simulators.

Named colors support.

Added wide gamut app icons.

Added a larger iOS marketing icon to the App Icon set.

Added option to preserve image vector data for matching Dynamic Type scaling.

Added support for HEIF images.

New in Xcode 9 – Swift static libary support.

• Added support for static library targets that contain Swift code.

New in Xcode 9 – Preview of a new build system written in Swift. Currently, This system is optional but it will become the default in a future version of Xcode

• Added a preview of a new build system written in Swift.

• Provides higher reliability.

• Catches many project configuration problems.

• Improves overall build-system performance.

  Note, build system performance does not include the compilers, linkers, and other tools used by the build system.

To opt into the new build system for a project or workspace, choose File > Project Settings or File > Workspace Settings, and then choose New Build System (Preview) for the Build System type. For notes on compatibility with existing projects, see the Xcode Release Notes.

New configurations for iOS hotspot and for Multipath TCP.

New network configurations, including content filtering, proxying DNS queries, and proxying TCP and UDP connections.

New background mode for watchOS for use with audio recording and turn-by-turn directions.

New mode for tvOS background fetch.

New in Xcode 9 – Core ML editor.

• Generate strongly typed interfaces for the model.

• Model compilation for on-device usage.

New in Xcode 9 – Network debugging for iOS and tvOS devices.

• Debug iOS and tvOS devices over WiFi or wired networks.

• Connect through Bonjour or enter an IP address.

• To enable network debugging, see Pair a wireless device in Xcode Help.

New in Xcode 9 – GPU frame capture and GPU overrides.

• View command buffers, attachments, resources, and call stacks.

• Modify shaders and save changes to your app.

• Move through the timeline for the sequence.

• Inspect and modify values for individual pixels in attachments including color values, alpha, depth, and more.

• Experiment with the rendering state without modifying code by minimizing texture bandwidth, minimizing number of rendered pixels, disabling the blending stage, showing only the wireframe, and scaling the amount of tessellation.

New in Xcode 9 – Undefined Behavior Sanitizer.

• Find sources of program crashes, unexpected behaviors, and incompatibilities with future versions of Xcode.

• Detect several types of undefined behaviors in C languages such as integer overflow, invalid casts, and alignment violations.

Enable the Undefined Behavior Sanitizer in the Diagnostics pane of the scheme editor.

New in Xcode 9 – Main Thread Checker.

• Detect AppKit, UIKit, and WebKit method calls that are not made on the main thread.

Automatically enabled during debugging, and can be disabled in the Diagnostic tab of the scheme editor. Use the Main Thread Checker with Swift and C languages.

Main Thread Checker works with Swift and C languages.

Enhanced the Breakpoint navigator with deep filtering.

Visual indicators for modified breakpoints.

Extended the view debugger to show view controllers, and to work with SceneKit and SpriteKit views.

Enhanced iOS energy gauge.

New unified browser that integrates reference, sample code, and articles.

Improved documentation search.

New jump bar for navigating between pages.

Integrated sample code downloading.

New split view for pinning graphs in the graphing area of a trace document.

Moved the strategy picker into a new toolbar at the top of the trace document and added a new All strategy.

Enhanced Metal debugging instrument.

Metal system trace VR support for viewing events such as compositor activity, pose queries, and more.

Named colors from the asset catalog.

New margin and baseline view constraints.

Auto Layout safe-area guides.

Full-screen watchOS apps.

New in Xcode 9 - Capture API.

• Define explicit capture boundaries in your code.

• Use the new MTLCaptureManager class and the new MTLCaptureScope protocol to set, manage, and trigger capture boundaries programatically.

• Use the extended Xcode GPU Capture UI to start and stop captures manually. You can also use Xcode to capture API boundaries defined in your app.

New in Xcode 9 - GPU counters.

• Analyze detailed profiling metrics about a specific GPU capture. In iOS and tvOS, GPU counters are shown as a timeline of command encoders; in macOS, GPU counters are shown as a timeline of draw or dispatch calls.

• Examine runtime performance of render or compute pipeline stages, such as the vertex shader, fragment shader, compute kernel, and more.

• Compare the amount of GPU time spent in each pipeline stage to find your performance bottlenecks.

New in Xcode 9 - GPU remarks.

• Find optimization opportunities in your Metal shading language code.

• Debug device-specific runtime issues in the shader editor.

• Follow direct resolutions and instructions to improve your code.

New in Xcode 9 - Smart filtering.

• Find specific debug information by typing into the debug navigator. Xcode dynamically displays suggestions as you type and highlight matching text, such as resources, pixel formats, function names, object labels, and more.

• Filter search results by selecting options from a predefined menu of Metal objects.

• Use multiple filters with many matching conditions.

New in Xcode 9 - Virtual Reality (VR) support.

• View VR submissions and left-eye/right-eye submitted surfaces.

Texture inspection for inspecting values of individual pixels in render targets, such as color, alpha, depth, and more.

Inspection of output vertex attributes in the buffer editor.

Data tips support for Metal objects such as textures, buffers and samplers.

Rename a symbol in a single file or in a project across Swift, C, Objective-C, C++ files, and Interface Builder files.

View all the possible changes in one editor pane.

Convert method signatures between Swift and Objective-C formats.

Update properties, getters, setters, and synthesized iVars as needed.

Apply a fix-it everywhere with one button.

Automatically fill in missing cases in switch statements, and mandatory methods for protocol conformance with one click.

Extract method functionality for all supported languages, along with other language-specific local refactoring.

New in Xcode 9 - Multiple concurrent simulators.

• Run multiple simulators at the same time.

• Run more tests in parallel.

• Test synching and other multidevice workflows.

New bezel for iOS and watchOS simulators includes the hardware controls. Use the bezel to move or resize the simulated device.

Share information with Simulator from Maps, Photos, and Safari.

Hold down the Option key when closing a simulated device or quitting Simulator to keep simulators running after closing the window or quitting Simulator for better integration with the simctl command of the xcrun command line tool.

Record videos of simulators.

Open the new Simulator documentation by choosing Help > Simulator Help.

New source control navigator for viewing branches, tags, and remote repositories for the current workspace.

New source control inspector shows details for the selected navigator item.

New editor for branch history including a jump bar for easy navigation.

New side-by-side editor for file diffs.

Easier and faster access to common tasks.

GitHub account integration for easy browsing and one-click creation of a project and the associated GitHub repository.

New in Xcode 9 – New source editor.

Faster and more versatile Find and replace.

Fast scrolling for files of any size.

Direct manipulation of code structure such as tokens and blocks.

Redesigned integration for source control.

Redesigned presentation of error and warning messages.

Support for Markdown.

New in Xcode 9 – Swift 4.

• One compiler for Swift 4 and Swift 3. You can compile Swift 4 and Swift 3 targets together in the same project.

• Improved migration experience that supports migrating only select targets to Swift 4. See, Migrate to Swift 4 @objc inference in Xcode Help.

• Faster generic code and decreased code size.

New in Xcode 9 – Parallel device testing.

Added new APIs to XCTest.

• Control and capture screenshots.

• Group test activities.

• Test attachments.

• Cleanup test state in a teardown block.

Target multiple apps in one UI test.

Run tests using a specified language and region.

New in Xcode 9 - Built in Xcode Server.

• New Server & Bots pane in Preferences for configuring Xcode Server and for setting Bot permissions.

Added support for 2-factor authentication.

Updated functionality for bots.

• Support automatic and manual provisioning workflows.

• Pass additional arguments to xcodebuild.

• Run tests in parallel on devices and Simulator.

• Configure language and region for tests.

• Send "all clear" emails notifications.