It's a strange time for us iOS beta testers. While Apple prepares for the general release of iOS 13 on Thursday, it's also beta testing that software's successor, iOS 13.1. An iPhone updated to iOS 13 on Sept. 19 will only have 11 days before seeing 13.1 in its Software Update page on Sept. 30. To prepare for this release, Apple released the fourth iOS 13.1 public beta, just about the same time as its developer counterpart.

The first point update for iOS 13 reintroduces features that were taken out of beta testing, most notable Shortcut Automations, ETA in Maps, and audio sharing with AirPods. We've also seen new icons in the volume HUD for paired audio devices, share sheet updates, and support for dynamic wallpapers, once only available on OLED iPhones.

It doesn't appear public beta 4 adds much in the way of new features or changes. We mainly see changes related to developers with the update, based on beta 4's release notes. We'll continue to update this article with any discoveries we come across:

iOS & iPadOS 13.1 Beta 4 Release Notes: Overview The iOS & iPadOS 13 SDK provides support for developing apps for iPhone, iPad, and iPod touch devices running iOS & iPadOS 13. The SDK comes bundled with Xcode 11 beta available from Beta Software Downloads. For information on the compatibility requirements for Xcode 11, see Xcode 11 Release Notes. Warning If your watch is running watchOS 6 beta, you must update it to watchOS 6 beta 2 or later before updating to iOS 13 beta 7 or later, otherwise your watch will no longer be able to connect to your phone. (52854192) General - Known Issues Snapshots for apps that use Metal might have an unexpected appearance in the App Switcher. (53121694) General - Deprecations The UIApplicationExitsOnSuspend key is no longer supported in iOS & iPadOS 13. Update your apps to handle modern multitasking. (43958234) Audio - New Features Voice Processing mode can now be enabled on AVAudioEngine. (50906329)

New AVAudioNode types can be used to wrap a user-defined block for sending or receiving data in real time.

A new method is available for an AVAudioEngine-based app to retrieve a list of all nodes attached to an AVAudioEngine instance.

A new rendering mode in AVAudioEnvironmentNode selects the best spatial audio rendering algorithm automatically based on the output device.

A new AVAudioSession property allows system sounds and haptics to play while the session actively uses audio input.

A new enumeration, AVAudioSession.PromptStyle, informs apps which style of voice prompt they should play based on other audio activity in the system.

AVAudioSession.RouteSharingPolicy now permits apps to specify route-sharing policies so their audio and video routes to the same location as AirPlay.

Audio Unit Extensions now support user presets that are available across all host applications. Audio - Deprecations The OpenAL framework is deprecated and remains present for compatibility purposes. Transition to AVAudioEngine for spatial audio functionality.

AUGraph is deprecated in favor of AVAudioEngine.

Inter-App audio is deprecated. Use Audio Units for this functionality moving forward.

Carbon component-based Audio Units are deprecated and support will be removed in a future release.

Legacy Core Audio HAL audio hardware plug-ins are no longer supported. Use audio server plug-ins for audio drivers moving forward. Audio Sharing - New Features Audio sharing is compatible with AirPods (1st generation or later) and PowerBeats Pro. iPhone 8 or later, iPad Pro 12.9-inch (2nd generation or later), iPad Pro 11-inch, iPad Pro 10.5-inch, iPad (5th generation or later), iPad Air (3rd generation), iPad mini (5th generation), or iPod touch (7th generation or later) is required. (51331268) AVFoundation - New Features AVFoundation now supports encoding video with alpha channels using HEVC. Videos encoded in this manner are broadly supported in AVFoundation APIs, and by Safari within web pages. Technical details of the format can be found in the Interoperability Profile specification. (8045917) Core Haptics - Known Issues By default, haptics are disabled when microphone recording begins. You can override this by setting the AVAudioSession property allowHapticsAndSystemSoundsDuringRecording to true before activating its audio session. (25811898)

Events — such as audioContinuous, hapticContinuous, and audioCustom — can't be resumed during the event; no output occurs for that event, only for subsequent events. This applies to playback at a specific time offset, seeking, and resuming. (29274583)

CHHapticDynamicParameter instances with nonzero relative times that are sent as part of a sendParameters(_:atTime:) call on a CHHapticAdvancedPatternPlayerwith the atTime parameter set to 0.0 are incorrectly applied at the beginning of the CHHapticPattern, instead of the expected nonzero relative time. This doesn't occur on a CHHapticPatternPlayer. (46316890)

Both vibrations generated through AudioServicesPlaySystemSound(_:) and vibration patterns generated through the user-created tap-to-vibrate UI are attenuated when compared to prior versions of iOS. (47448156)

Parameter Curves are not supported with a CHHapticAdvancedPatternPlayer, only a CHHapticPatternPlayer. No error is generated when a CHHapticPattern containing a Parameter Curve is passed to a CHHapticAdvancedPatternPlayer. (47891515)

Brief audio distortion occurs when starting a Playback category app such as Music in the background. For example, brief distortion occurs if you start the app from Control Center while Core Haptics audio playback using a playAndRecord audio session is already underway. (48121467)

Following any decompression to uncompressed floating-point samples, the total limit on all audioCustom resources per process is eight megabytes. (48659023)

Multiple overlapping Parameter Curves for the same CHHapticDynamicParameter.IDmight result in playback artifacts. (50026384)

The maximum duration for a hapticContinuous haptic event is 30 seconds. Events exceeding this limit can be constructed and accepted by CHHapticPatternPlayer, but haptic playback will fade out after 30 seconds. (51322525)

There is a limit of 16 control points for any type of Parameter Curve. If more control points are desired, create additional parameter curves for consecutive windows of time for the same parameter. (49486454) Core Image - New Features The init(imageURL:options:) and init(imageData:options:) initializers no longer support RAW version 5 and earlier. Version 6 and later remain supported. (50911303)

Added new APIs for instantiating and modifying the built-in Core Image filters.

The CICoreMLModel filter is enhanced to support models with an input or output of type MLFeatureType.multiArray.

Metal CIKernel instances support arguments with arbitrarily structured data.

Metal CIKernel instances support returning a group of 2 × 2 pixels.

The integer values of CIFormat symbols, such as ARGB8, have changed to a new set of values that are consistent across platforms. The former values remain supported for backward compatibility; however, you should avoid dependancies on specific numerical values. Find My - Known Issues When performing an action in Find My that generates an email, you might see references to the Find My Friends and Find My iPhone apps. (51123613)

While iOS & iPadOS 13 remains in beta, offline-finding capability is limited. iCloud - Known Issues You might be unable to delete the Recovered Files folder in On My iPad/iPhone. (54785368) Workaround: Back up your device, erase it, restore from backup, then try again.

Back up your device, erase it, restore from backup, then try again. After updating to iOS 13 beta 6, iCloud Drive might synchronize for an extended period of time. If you notice any missing files, they can be found in a Recovered Files folder under On My iPhone/iPad within the Files app. (53772753)

When creating a new Pages, Numbers, or Keynote document in a shared folder, you might see the message: "Couldn't connect to iCloud." (50827963) Workaround: Close and reopen the document. Mail - New Features Ignore Blocked Senders can now be enabled in Settings > Mail. The blocked contacts list is shared with Messages, FaceTime, and Phone. (50775961) Media Player - Resolved Issues Fixed an issue where playback stopped if an app using MediaPlayerFramework to play catalog content was backgrounded. (54131440) Metal - Known Issues In iOS 13, if you refer to a sparse texture in an argument buffer you must explicitly call use(:usage:stages:) on the texture rather than calling useHeap(:) on the heap. (54605833) Networking - New Features To enhance security, URLSession no longer sniffs the MIME type when the server sends Content-Type: application/octet-stream. (7820658)

NSURLRequest.CachePolicy.reloadRevalidatingCacheData and NSURLRequest.CachePolicy.reloadIgnoringLocalAndRemoteCacheData APIs are now available. (49660334)

Starting with iOS 13 beta 4, the copy attribute of the httpBodyStream property of NSMutableURLRequest is enforced. If the body data is mutated after the property setter has been called, data sent in the HTTP request won't include that mutation. Invoking the property getter no longer returns a NSMutableData reference, even when the setter was invoked with data of that type. As of iOS 13 beta 5, apps built using the iOS 12 SDK or previous SDKs use the legacy behavior. (53427882)

The CNCopyCurrentNetworkInfo API has changed to address privacy. Please refer to the updated API documentation and headers for more details. (52707167)

All URLSessionTask instances with a GET HTTP method that contain a body now produce the error NSURLErrorDataLengthExceedsMaximum. (46025234) Networking - Deprecations Removed support for FTP and File URL schemes for Proxy Automatic Configuration (PAC). HTTP and HTTPS are the only supported URL schemes for PAC. This affects all PAC configurations including, but not limited to, configurations set using Settings, System Preferences, Profiles, and URLSession APIs such as connectionProxyDictionaryand CFNetworkExecuteProxyAutoConfigurationURL(_:_:_:_:). (28578280)

The URLSession and NSURLConnection APIs no longer support SPDY. Servers should use HTTP 2 or HTTP 1.1. (43391641) RealityKit - Known Issues The camera feed will remain visible at the base of objects loaded from a Reality File when ARView.Environment.Background is set to ARView.Environment.Background.skybox(_:) (53715030) — Workaround: Turn off grounding shadows when setting the background to ARView.Environment.Background.skybox(_:) by setting ARView.RenderOptions to disableGroundingShadows. Screen Time - Known Issues If you enable Share Across Devices, Screen Time settings don't sync with iCloud until your iOS device is restarted. Any edits you make to your Screen Time settings on that device before restarting are lost. (50194586) Sidecar - Known Issues To use Sidecar with iPadOS 13.1 beta 2 or later, macOS Catalina Beta 8 or later is required. (54903543) Siri - Known Issues The supportsOnDeviceRecognition property always returns false the first time it's accessed. After a few seconds, accessing it again returns the correct value. (47822242)

Shortcuts opened on iOS & iPadOS 13 beta are automatically upgraded and can no longer be opened on iOS 12. If a device with iOS 12 and a device with iOS 13 share an iCloud account, shortcuts might become unusable on the device running iOS 12. (50873839) Workaround: Disable iCloud Sync between devices running iOS & iPadOS 13 beta and devices running iOS 12.

Disable iCloud Sync between devices running iOS & iPadOS 13 beta and devices running iOS 12. Currently, the only supported response for INSearchForMediaIntent is INSearchForMediaIntentResponseCode.continueInApp. (51010311) SwiftUI - New Features You can now create a Color from a UIColor or NSColor. (49833933)

NSManagedObject now conforms to ObservableObject. The new @FetchRequestproperty wrapper can drive views from the results of a fetch request, and managedObjectContext is now included in the environment. (50280673)

Gesture modifiers are renamed for consistency. For example, tapAction(count:_:) is renamed onTapGesture(count:perform:), and longPressAction(minimumDuration:maximumDistance:_:pressing:) is renamed onLongPressGesture(minimumDuration:maximumDistance:pressing:perform:). (50395282)

Text now has a default line limit of nil so that it wraps by default. (51147116)

ContentSizeCategory and several other enumerations are now CaseIterable. (51168712)

SegmentedControl is now a style of Picker. (51769046)

BindableObject is replaced by the ObservableObject protocol from the Combine framework. (50800624) You can manually conform to ObservableObject by defining an objectWillChangepublisher that emits before the object changes. However, by default, ObservableObjectautomatically synthesizes objectWillChange and emits before any @Publishedproperties change. // RoomStore.swift

import Foundation class RoomStore: ObservableObject {

@Published var rooms: Room =

} struct Room: Identifiable {

var id: UUID

var name: String

var capacity: Int

var hasVideo: Bool

} // ContentView.swift

import SwiftUI struct ContentView: View {

@ObservedObject var store: RoomStore var body: some View {

NavigationView {

List(store.rooms) { room in

RoomCell(room: room)

}

.navigationBarTitle("Rooms")

}

}

}

@ObjectBinding is replaced by @ObservedObject. The Identifiable protocol is now part of the Swift standard library. As a result, your model files no longer need to import the SwiftUI framework. (SE-0261)

The EnvironmentValues structure has four new properties for reading accessibility values from the environment: accessibilityDifferentiateWithoutColor, accessibilityReduceTransparency, accessibilityReduceMotion, and accessibilityInvertColors. (51712481)

The color(_:) modifier for Text is renamed foregroundColor(_:) for consistency with the more general foregroundColor(_:) view modifier. (50391847)

The BindableObject protocol's requirement is now willChange instead of didChange, and should now be sent before the object changes rather than after it changes. This change allows for improved coalescing of change notifications. (51580731)

The RangeReplaceableCollection protocol is extended to include a remove(atOffsets:) method and the MutableCollection protocol is extended to include a move(fromOffsets:toOffset:) method. Each new method takes IndexSetinstances that you use with the onMove(perform:) and onDelete(perform:)modifiers on ForEach views. (51991601)

Added improved presentation modifiers: sheet(isPresented:onDismiss:content:), actionSheet(isPresented:content:), and alert(isPresented:content:) — along with isPresented in the environment — replace the existing presentation(_:), Sheet, Modal, and PresentationLink types. (52075730)

Updated the APIs for creating animations. The basic animations are now named after the curve type — such as linear and easeInOut. The interpolation-based spring(mass:stiffness:damping:initialVelocity:) animation is now interpolatingSpring(mass:stiffness:damping:initialVelocity:), and fluidSpring(stiffness:dampingFraction:blendDuration:timestep:idleThreshold:) is now spring(response:dampingFraction:blendDuration:) or interactiveSpring(response:dampingFraction:blendDuration:), depending on whether or not the animation is driven interactively. (50280375)

Added an initializer for creating a Font from a CTFont. (51849885)

You can style a NavigationView using two new style properties: StackNavigationViewStyle and DoubleColumnNavigationViewStyle. By default, navigation views on iPhone and Apple TV visually reflect a navigation stack, while on iPad and Mac, a split-view styled navigation view displays. (51636729) When using the DoubleColumnNavigationViewStyle style, you can provide two views when creating a navigation view — the first is the master and the second is the detail. For example: NavigationView {

MyMasterView()

MyDetailView()

}

.navigationViewStyle(DoubleColumnNavigationViewStyle()) SwiftUI - Known Issues Apps containing SwiftUI inside a Swift package might not run on versions of iOS earlier than iOS 13. (53706729) Workaround: When back-deploying to an OS which doesn't contain the SwiftUI framework, add the -weak_framework SwiftUI flag to the Other Linker Flags setting in the Build Settings tab. See Frameworks and Weak Linking for more information on weak linking a framework. This workaround doesn't apply when using dynamically linked Swift packages which import SwiftUI. SwiftUI - Deprecations SwiftUI APIs deprecated in previous versions of iOS 13 beta have been removed. (53310683)

NavigationDestinationLink and DynamicNavigationDestinationLink are deprecated; their functionality is now included in NavigationLink. (50630794)

The Length type is replaced by CGFloat. (50654095)

TabbedView is now named TabView. (51012120)

HAlignment and VAlignment are now deprecated, use the more flexible HorizontalAlignment or VerticalAlignment types instead and use TextAlignment for text. (51190531)

The SelectionManager protocol is removed, use Optional and Set instances directly for selection. (51557694)

The isPresented environment value is deprecated and replaced with the more general presentationMode value. (51641238)

The StaticMember protocol is deprecated. Use protocol-conforming types directly instead. For example, use an instance of WheelPickerStyle directly rather than the wheel static member.(52911961)

Complex overloads for the background(_:alignment:) and border(_:width:)modifiers are deprecated. Use shapes in a background(_:alignment:) or overlay(_:alignment:) to draw these instead. (53067530)

SwiftUI APIs deprecated in previous betas are now removed. (52587863)

The identified(by:) method on the Collection protocol is deprecated in favor of dedicated init(_:id:selection:rowContent:) and init(_:id:content:)initializers. (52976883, 52029393) The retroactive conformance of Int to the Identifiable protocol is removed. Change any code that relies on this conformance to pass \.self to the id parameter of the relevant initializer. Constant ranges of Int continue to be accepted: List(0..<5) {

Text("Rooms")

} However, you shouldn't pass a range that changes at runtime. If you use a variable that changes at runtime to define the range, the list displays views according to the initial range and ignores any subsequent updates to the range. Several extensions to the Binding structure are removed. (51624798) If you have code such as the following:

struct LandmarkList: View {

var landmark: Landmark

@Binding var favorites: Set<Landmark> var body: some View {

List(landmarks) { landmark in

Toggle(landmark.name, isOn: self.$favorites.contains(landmarkID))

}

}

} Define the following subscript on the Set structure:

extension Set {

subscript(member: Element) -> Bool {

get { contains(member) }

set {

if newValue {

insert(member)

} else {

remove(member)

}

}

}

}

Then, change self.$favorites.contains(landmarkID) to self.$favoriteslandmarkID. The Binding structure's conditional conformance to the Collection protocol is removed. (51624798) If you have code such as the following:

struct LandmarkList: View {

@Binding var landmark: Landmark var body: some View {

List(landmarks) { landmark in

Toggle(landmark.value.name, isOn: landmark\.isFavorite)

}

}

}

Define the following collection type:

struct IndexedCollection<Base: RandomAccessCollection>: RandomAccessCollection {

typealias Index = Base.Index

typealias Element = (index: Index, element: Base.Element) let base: Base var startIndex: Index { base.startIndex } var endIndex: Index { base.startIndex } func index(after i: Index) -> Index {

base.index(after: i)

} func index(before i: Index) -> Index {

base.index(before: i)

} func index(_ i: Index, offsetBy distance: Int) -> Index {

base.index(i, offsetBy: distance)

} subscript(position: Index) -> Element {

(index: position, element: baseposition)

}

} extension RandomAccessCollection {

func indexed() -> IndexedCollection<Self> {

IndexedCollection(base: self)

}

} Then, update your code to:

struct LandmarkList: View {

@Binding var landmarks: Landmark var body: some View {

List(landmarks.indexed(), id: \.1.id) { (index, landmark) in

Toggle(landmark.name, isOn: self.$landmarksindex.isFavorite)

}

}

} The relativeWidth(_:), relativeHeight(_:), and relativeSize(width:height:) modifiers are deprecated. Use other modifiers like frame(minWidth:idealWidth:maxWidth:minHeight:idealHeight:maxHeight:alignment:) instead. (51494692) Third-Party Apps - Known Issues You might be unable to stream to a Chromecast device. (51334673) UIKit - New Features The UITableViewCell class no longer changes the backgroundColor or isOpaqueproperties of the contentView and any of its subviews when cells become highlighted or selected. If you are setting an opaque backgroundColor on any subviews of the cell inside (and including) the contentView, the appearance when the cell becomes highlighted or selected might be affected. The simplest way to resolve any issues with your subviews is to ensure their backgroundColor is set to nil or clear, and their opaqueproperty is false. However, if needed you can override the setHighlighted(_:animated:) and setSelected(_:animated:) methods to manually change these properties on your subviews when moving to or from the highlighted and selected states. (13955336)

Since iOS 8, using UISearchController with UINavigationController has required setting the definesPresentationContext property of the top view controller to true. Failure to do so leads to subtle bugs that can be hard to detect and debug. Starting in iOS & iPadOS 13 beta, if a view controller's navigationItem has a non-nilsearchController, when the view controller is shown in a navigation controller, UINavigationController automatically sets that view controller's definesPresentationContext property to true. If you are targeting earlier versions of iOS, set this property before your search controller becomes active. (31338934)

The UIRefreshControl class no longer directly modifies the contentInset of its scroll view. Instead, its adjustments to the content inset will be incorporated into the scroll view's adjustedContentInset. The only exception is when the scroll view's contentInsetAdjustmentBehavior is set to UIScrollView.ContentInsetAdjustmentBehavior.never, in which case the UIRefreshControl instance will modify the contentInset directly as it did in previous releases. (35866834)

If you implement self-sizing cells in a UITableView by overriding sizeThatFits(_:)without using Auto Layout, the height you return is interpreted as the desired height for the contentView of the cell, and UITableViewCell automatically adds any additional height needed to allow room for the cell separator. If you implement manual self-sizing this way, the cell's contentView width is guaranteed to be accurate for you to use in manual layout calculations when sizeThatFits(_:) is called on the UITableViewCell. (39742612)

Trait environments, such as views and view controllers, now have their traitCollectionproperty populated with traits during initialization. These initial traits represent a prediction of the ultimate traits that the trait environment will receive when it gets added to the hierarchy. Because the traits that are populated during initialization are just a prediction, they might differ from the traits that are received once actually in the hierarchy. Therefore, when possible you should wait to perform work that uses the traitCollection until the view, or view controller's view, has moved into the hierarchy — meaning window returns a non-nil value — so that you don't have to throw away any work done using the predicted traits if the actual traits are different. The best time to use the traitCollection is during layout, such as inside layoutSubviews(), viewWillLayoutSubviews(), or viewDidLayoutSubviews().

The traitCollectionDidChange(_:) method is only called when the value of a trait changes. Importantly, because the trait collection is now initialized to a prediction of the ultimate traits in the destination hierarchy, when the initial predicted traits match the ultimate traits in the hierarchy, traitCollectionDidChange(_:) will not be called when the trait environment is added to the hierarchy. Because traitCollectionDidChange(_:) is intended to be an invalidation callback to notify you that one or more traits changed, audit your existing implementations of this method, as well as the UIContentContainer method willTransition(to:with:), for places where you might have been relying on it to trigger initial setup. The best place to lazily perform work that uses the traitCollection is inside one of the layoutSubviews methods discussed above, but remember that these layout methods are called any time layout occurs so be sure to avoid repeating work when you don't need to. (46818941)

You can now enable debug logging to easily see when traitCollectionDidChange(_:) or willTransition(to:with:) is called on your own classes. Turn on the logging by using the following launch argument: -UITraitCollectionChangeLoggingEnabled YES. You might want to temporarily disable the Main Thread Checker while using this launch argument and running your app from Xcode to avoid extra log messages for unrelated classes. (47858564)

The UITableViewCell class's contentView property is always laid out edge-to-edge with adjacent accessories, both on the leading and the trailing side. This streamlines the layout code so developers who want the correct default offset no longer have to align their content with the content view border or the layout margin depending on whether there is an accessory on the trailing side or not. You should now always lay out their code on the layout margins of the cell's content view to get the default system insets. These insets will be adjusted automatically based on the accessories visible in the cell to match the system's default spacing. (48214114)

You can now invoke a custom initializer from a creation block that's passed through instantiateInitialViewController(creator:) or instantiateViewController(identifier:creator:). This makes it possible for you to initialize view controllers with additional context and arguments, while taking advantage of defining them in a storyboard through Interface Builder. A custom controller initializer must call its super.init(coder:) method and pass the coder argument that it receives through the creation block. (48313869) UIKit - Known Issues Specifying UIWindowScene.DestructionRequestOptions in Swift is currently unavailable. (51036709) UIKit - Resolved Issues Three-finger productivity gestures no longer open an editing menu when text entry fields aren't present. (54433338)

Apps are now able to override UIEditingInteractionConfiguration to suppress three-finger tap gestures. (53984454) Voice Analytics - Known Issues Voice Analytics is currently available only when using server based speech recognition. (53604093) Watch - Known Issues Complications might disappear from Apple Watch after updating to iOS 13 beta if your watch isn't running watchOS 6 beta. (50507942) Xcode - New Features CAMetalLayer is now available in Simulator. (45101325)

To download and install iOS 13.1 public beta 4, sign up through Apple's beta site, download and install the configuration profile, then update over the air. If you already have the profile, go to Settings –> General –> Software Update to begin the installation of the latest beta build, or you can wait until it installs automatically if "Automatic Updates" is enabled.