Starting in iOS 26, two notable changes have been made to CallKit, LiveCommunicationKit, and the PushToTalk framework: As a diagnostic aid, we're introducing new dialogs to warn apps of voip push related issue, for example when they fail to report a call or when when voip push delivery stops. The specific details of that behavior are still being determined and are likely to change over time, however, the critical point here is that these alerts are only intended to help developers debug and improve their app. Because of that, they're specifically tied to development and TestFlight signed builds, so the alert dialogs will not appear for customers running app store builds. The existing termination/crashes will still occur, but the new warning alerts will not appear. As PushToTalk developers have previously been warned, the last unrestricted PushKit entitlement ("com.apple.developer.pushkit.unrestricted-voip.ptt") has been disabled in the iOS 26 SDK. ALL apps that link against the iOS 26 SDK which receive a voip push through PushKit and which fail to report a call to CallKit will be now be terminated by the system, as the API contract has long specified. __ Kevin Elliott DTS Engineer, CoreOS/Hardware

We are encountering the following issue with our VoIP application for iPhone, published on the App Store, and would appreciate your guidance on possible countermeasures. The VoIP application (callee side) utilizes a Wi-Fi network. The sequence leading to the issue is as follows: VoIP App (callee): Launches iPhone (callee): Locks (e.g., by short-pressing the power button) VoIP App (callee): Transitions to a suspended state VoIP App (caller): Initiates a VoIP call VoIP App (callee): Receives a local push notification VoIP App (callee): Creates a UDP socket for call control (for SIP send/receive) VoIP App (callee): Creates a UDP socket for audio stream (for RTP send/receive) VoIP App (callee): Exchanges SIP messages (INVITE, 100 Trying, 180 Ringing, etc.) using the call control UDP socket VoIP App (callee): Answers the incoming call VoIP App (callee): Executes performAnswerCallAction() Immediately after executing performAnswerCallAction() in the above sequence, the sendto() function for both the "UDP socket for call control (SIP send/receive)" and the "UDP socket for audio stream (RTP send/receive)" occasionally returns errno = 57 (ENOTCONN). (of course The VoIP app itself does not close the sockets in this timing) Given that the user has performed an answer operation, the iPhone is in an active state, and the VoIP app is running, what could be the possible reasons why the sockets suddenly become unusable? Could you please provide guidance on how to avoid such socket closures? Our VoIP app uses SCNetworkReachabilitySetCallback to receive network change notifications, but no notifications regarding network changes were received at the time errno = 57 occurred. Is it possible for sockets used by an application to be closed without any notification to the application itself?

We are encountering the following issue with our VoIP application for iPhone, published on the App Store, and would appreciate your guidance on possible countermeasures. The VoIP application (callee side) utilizes a Wi-Fi network. The sequence leading to the issue is as follows: VoIP App (callee): Launches iPhone (callee): Locks (e.g., by short-pressing the power button) VoIP App (callee): Transitions to a suspended state VoIP App (caller): Initiates a VoIP call VoIP App (callee): Receives a local push notification VoIP App (callee): Answers the incoming call VoIP App (callee): Executes performAnswerCallAction() After this, the VoIP App (callee) uses "NSTimer scheduledTimerWithTimeInterval" to manage internal processing timing. However, the processing sometimes takes longer than the specified waiting time. Specifically, delays of several seconds can occur. We understood that if the user is interacting with the screen and both the iPhone and the VoIP app are in an active state, the VoIP app's processing would not be delayed. However, can significant delays (several seconds) in application processing still occur even when the iPhone is in an active state (i.e., the user is interacting with the screen)?"

My iPhone VoIP app, which I'm developing, uses Apple Push Notification service (APNs). I have a question regarding the following statement found in "[Overview of app transfer > Apps using push notifications]" Overview of app transfer You must manually reestablish push notification services if transferring an app that uses the Apple Push Notifications service (APNs). The recipient must create a new client SSL certificate using their developer account, as associated client SSL certificates, TLS certificates, and authentication tokens aren’t transferred. Question Let's say the recipient of the app transfer creates a "new SSL certificates, TLS certificates, and authentication tokens." Afterward, we need to verify that the Apple Push Notification service (APNs) works correctly when combining the transferred app with this "new SSL certificates, TLS certificates, and authentication tokens." However, until the recipient finishes verifying that it works correctly, the transferor want to keep the app available for download as before and be able to use the Apple Push Notification service. Is this possible? More specifically, can the recipient test the app to be transferred on TestFlight "before the transfer is completed"? I want to combine it with the "new SSL certificates, TLS certificates, and authentication tokens." and test it on TestFlight. Reading "[Initiate an app transfer]," it mentions the existence of a "Pending App Transfer" status. During this "Pending App Transfer" status, can the recipient test the app on TestFlight? Initiate an app transfer After you initiate the transfer, the app stays in its previous status, with the Pending App Transfer status added, until the recipient accepts it or the transfer expires after 60 days. Also, if there are any documents describing these procedures, I would appreciate it if you could share them. Thank you very much.

My app uses CallKit and PushKit for real-time voice and video calls. I want to configure VoIP push notifications so incoming calls can wake the app, even when it’s in the background or terminated. Right now, I only see the normal Push Notifications option in my App ID settings and no VoIP Services section.

Hello, We are facing issue that sometimes a voip notification gets delivered after it is expired. The issue can be simply demonstrated we set the device to flight mode, and after 20s we disable flight mode. We still receive the voip notification. We are setting the expiration header as following apns-expiry=0, so from my understanding it should not be delivered if the device was not able to receive the notification in the fist attempt. I have read following thread https://developer.apple.com/forums/thread/778512, from which I understand this is a long standing issue. Hence my question is, is there any way how we can notify the call kit that the call is actually no longer valid, and do not display the call to the user at all? Currently we are forced to always display CallKit call when the notification comes, and some of our users are confused that they see a missed call which they did not have any chance to pick up. Please let me know if you need any more information. Best Regards, Adam Chlupacek

We are trying to figure out a strange issue. Our app has not changed for at least 10 months but my devices and the QA tester device have all stopped receiving push/call notifications for twilio voip The twilio credential and apple voip services certificate are in date and valid It is pointing to the correct bundle id and topic (not changed configuration for years) token passed in to TwilioVoiceSDK.register() is retrieved from PKPushRegistry as per guide Running locally the Twilio Voice SDK successfully registers and retrieves APNs token What is interesting is if I log in with exactly the same client account on an iOS 18.5 device (and an older iPad) call notifications work perfectly (I have made sure all focus modes/dnd are off and notification settings are identical) The only changes myself and QA have made recently is minor iOS 18 version updates - 18.6.2 and 18.7.1 These now receive Invalid device token from APNs when Twilio attempts to create a call/voip notification for the user identity Our devices sometimes switch environments test/prod so I installed the app cleanly on a borrowed 18.6.2 device and got the exact same issue We have tested on these devices most of the year with no issues. I have been in touch with twilio support and added code to explicitly unregister and re register on an affected device to clear any bindings but it didn't help. Have apple made any changes in PushKit or token behaviour for later versions of iOS 18? Thanks

We are facing an issue where VoIP notifications are not delivered to a user's device. If we login with the user credentials on another device the VoIP notifications are being received, if he logs in on his device VoIP notifications are not being received anymore on all devices. So When the user logs in on the affected device, all devices on that account stop receiving VoIP pushes (including the affected one). Logging out on the affected device restores delivery to other devices. What could cause this issue? It's only happening for this user so the configuration and mobile app PushKit code is working as intended.

Hi all, May I please ask for an official clarification or documentation reference from Apple regarding this scenario: Is it possible for an iOS app to automatically launch or open a specific screen when a push notification is received — while the app is in the background or terminated (killed) state? I understand that for most cases, user interaction (such as tapping the notification) is required before the app can show UI. However, I’d like to confirm whether this is also true for time-sensitive or critical alert notifications, including emergency use cases (e.g. public safety alerts). Specifically: Can a critical alert notification directly launch the app or present a view controller? Or is user interaction always required before the app can present any UI, even with the critical alert entitlement? I would appreciate if anyone — especially Apple staff or engineers — could share an official Apple document or statement that confirms this behavior. Thank you very much! (Use case context: I’m developing an emergency broadcast feature for a property management / tenant app.)

I am an iOS development engineer. Recently, I updated the Xcode version to 16.1 (16B40) and updated my debugging device (iPhone 15) to iOS 18.1.1. However, I found that I could not respond to the delegate method. I confirmed that my code, certificate, Xcode settings, and network environment had not changed. Simply executing application.registerForRemoteNotifications() in func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool did not receive a response(didRegisterForRemoteNotificationsWithDeviceToken or didFailToRegisterForRemoteNotificationsWithError ). In the same environment, when I switched to another device for debugging (iOS 17.0.3), the delegate method would respond. I really don't know what to do, I hope someone can help me, I would be very grateful. Please note: Everything is normal when using devices before iOS 18.1.1 version

Hello Team, We are currently experiencing an issue where some of our devices are not receiving push notifications. We are sending notifications via the Apple Push Notification portal (https://developer.apple.com/notifications/push-notifications-console/) using the following two requests. However, in both cases, the notifications are not being delivered to the devices. Scenario 1 : When we send a request with apns-push-type set to alert, we receive the following error. Request : curl -v --header "authorization: bearer ${AUTHENTICATION_TOKEN}" --header "apns-topic: com.testcompany.sampletest" --header "apns-push-type: alert" --header "apns-priority: 10" --header "apns-expiration: 0" --data '{"aps":{"alert":{"title":"Test Notification Title","subtitle":"Test Notification Sub Title","body":"Test Notification Body"}}}' --http2 https://api.push.apple.com:443/3/device/*devicetoken* Response: { "code": 400, "message": "bad-request", "reason": "The device token is inactive for the specified topic. There is no need to send further pushes to the same device token, unless your application retrieves the same device token.", "requestUuid": "c4ae39b4-87e1-4269-a1e9-163f60ec0385" } Scenario 2 : However, if we send the request with apns-push-type set to background, the request is processed successfully by APNs, but no notification is received on the device. Request : curl -v --header "authorization: bearer ${AUTHENTICATION_TOKEN}" --header "apns-topic: com.testcompany.sampletest" --header "apns-push-type: background" --header "apns-priority: 10" --header "apns-expiration: 0" --data '{"aps":{"alert":{"title":"Test Notification Title","subtitle":"Test Notification Sub Title","body":"Test Notification Body"}}}' --http2 https://api.push.apple.com:443/3/device/*devicetoken* Response: Getting a message that The notification sent successfully but no notification is received on the device. In both cases (with alert and background push types), the push notification does not reach the device. Additionally, when we validated the device token using the APNs Device Token Validator, it appears to be valid and returns the following message. "Device Token is valid for sending Alert & Background push-type notifications in the Production environment" Affected Device: macOS version : MacOS 15.3.1 Processor : Apple M1 Could you please assist me in resolving this issue? Thanks

I am developing a Flutter app for food delivery (a multivendor e-commerce restaurant app). In the vendor app (Android), I successfully implemented a background notification that stays active until the vendor responds with either Accept or Decline. This works fine on Android, but I cannot get the same functionality working on iOS. My requirements: Vendor should receive a background notification. The notification should include action buttons (Accept / Decline). It should remain active until the vendor takes action. My questions: Is this possible to implement in iOS with Flutter? If yes, what is the recommended way (e.g., firebase_messaging, flutter_local_notifications, flutter_foreground_task, or native iOS integration)? Are there any iOS restrictions I should consider compared to Android background services? I built this for Android using firebase_messaging + flutter_foreground_task + flutter_local_notifications. On iOS, I tried setting up firebase_messaging and flutter_local_notifications, but I’m unable to keep the notification persistent with Accept/Decline action buttons. I expected similar behavior to Android, but it seems iOS has more restrictions around background services and notification handling. Dependencies I am using (relevant ones): firebase_core: ^3.8.0 firebase_messaging: ^15.1.5 flutter_local_notifications: ^17.2.2 flutter_foreground_task: ^8.17.0 get: ^4.7.2 shared_preferences: ^2.3.2

Hello Developers, I am currently developing a Flutter application where I am implementing both push notifications (for messages) and VoIP call notifications. The implementation works perfectly fine on Android. However, I am facing issues specifically on iOS in the following scenarios: Terminated State: When the app is terminated on iOS, neither call notifications nor message notifications are received. In the background state, things partially work, but in the terminated state, nothing comes through. Debug vs Production: In Debug mode, everything works as expected (both message and call notifications). Once I release the app to TestFlight (Production), the notifications completely stop working: Message notifications are not delivered at all. Call notifications also fail to appear in terminated state. Configuration Details: I have already configured APNs with .p8 key in Firebase. The required capabilities (Push Notifications, Background Modes → Remote notifications, VoIP, etc.) are enabled in Xcode. I also updated the AppDelegate.swift / Notification handling code for production environment. Despite these steps, the same issue persists in production/TestFlight. It seems like the issue is specifically related to production environment handling on iOS, since everything works in debug. My Question: What could be causing push notifications and call notifications to not work in the terminated state on iOS, especially in production/TestFlight builds? Are there additional configuration steps required for APNs, VoIP, or background handling in production that differ from debug mode? Any guidance or similar experiences would be really helpful. Thanks in advance for your support.

Hi everyone, on iOS, when a VoIP call arrives and the user accepts it from the lock screen (after unlocking with Face ID/Touch ID), is there any way to automatically bring my app to the foreground and show the in-app call screen, instead of staying in the system CallKit UI?

An issue with the CallKit UI, specifically regarding the functionality of the speaker button. When a user initiates a video call with CallKit and then, using the existing CallKit session, initiates an audio call, there are no issues with CallKit or the audio. However, if the user terminates the video call from the CallKit UI, the active CallKit session ends. To resume the ongoing audio call, we report a new CallKit call upon the end call trigger. While there are no issues with this reporting, the CallKit UI does not provide an audio route for the built-in receiver, and the speaker button remains unresponsive. IPA was build on SDK 18 and running on iOS beta 26. Issue is NOT seen with SDK18 and running iOS 18.x or lower devices. Feedback - FB18855566

We are currently developing a VoIP application that supports Local Push extention. We discovered an issue with this app where the performEndCallAction response to reportCallWithUUID is occasionally slow.(See below for detail) It usually works without any issues, so we believe there is no problem with the app's processing flow. This issue only occurs very rarely, but each time it does there is a delay of about 60 seconds, which leads us to suspect that there is some kind of problem on the iOS side, and that fail-safe processing is occurring after 60 seconds. Do you know of a workaround for this issue?

iOSアプリでNEAppPushSessionを使い、NEAppPushDelegateの通知を受けてCallKitの着信画面を表示する実装をしていますが、以下の問題に直面しています。 8/13 ログにて下記のエラーが頻発しました。 通知の受け取りテストを約120回してその間ずっとこのエラーが出ていました。 エラー 2025-08-14 11:27:06.793073 +0900 nesessionmanager NESMAppPushSession[SimplePushDefaultConfiguration:7B7218F3-94B5-4AE5-9B9E-94E176694D02] failed to report incoming call to CallKit, error: Error Domain=NSCocoaErrorDomain Code=4099 "The connection to service named com.apple.callkit.networkextension.messagecontrollerhost was invalidated from this process." UserInfo={NSDebugDescription=The connection to service named com.apple.callkit.networkextension.messagecontrollerhost was invalidated from this process.} このエラーログが頻発した後、callkitの通知画面が表示されなくなりました。 ですがどうやら通知の監視は開始しているようです。 15時間後の8/14 時間をあけたからか、再度通知が来るようになりました。 ですが再度通知の受け取りテストを行った時に同じエラーログが出ました。 再度通知テストを約120回程行ったら、このエラーログが頻発した後、callkitの通知画面が表示されなくなりました。 ですがどうやら今回も通知の監視は開始しているようです。 15時間後の8/15 今日は15時間かけても通知を取得できませんでした。 ですが同じく通知の監視は開始していそうです。 iPhoneの再起動、Xcodeのクリーンアップ、アンインストールして再インストールなどしても通知は来ないままでした。 また、不思議なことに通知が来ない事象が起きた端末以外でも同じように通知を取得することができません。 他の通知は受け取ることができますが独自の通知であるNEAppPushManagerだけ通知を取得することができません。 質問です。 再度通知を出すためには何をすれば良いでしょうか。 この事象は4099エラーを出しすぎたことにより発生する障害なのでしょうか。 4099エラーを出ている原因は何でしょうか。

I am currently implementing VoIP push notifications in my iOS app using PushKit. On iOS 18, I am able to receive VoIP notifications successfully when the app is in the foreground. However, when the app is in the background or in a terminated (kill) state, the notifications do not arrive. In earlier iOS versions, my existing implementation worked as expected across all app states. This issue seems to have started after testing on iOS 18, which appears to have introduced stricter permission or background execution requirements. Questions: Has iOS 18 introduced new permission requirements or entitlements for VoIP push notifications? Do I need to explicitly request a new type of user permission for VoIP notifications? Are there additional background modes, Info.plist keys, or PushKit changes required for VoIP to work in background and terminated states on iOS 18? Additional Information: . Foreground: Works fine, pushRegistry(_:didReceiveIncomingPushWith:for:completion:) is triggered. . Background/Terminated: No call to the above delegate method. . Using correct voip push type in the payload. . PushKit is configured in AppDelegate. . Background modes for "Voice over IP" and "Background Processing" are enabled. . Using a real device with iOS 18 for testing (not simulator). Any guidance or updated documentation references for handling VoIP pushes in iOS 18 would be greatly appreciated.

Good afternoon, Our team is currently developing a mobile application that includes video call functionality, and we are seeking the optimal approach to enable incoming calls on iOS devices. Ideally, we would like calls to be delivered even when the app is completely closed or after the device is restarted. As I understand it, this may require obtaining VoIP permissions; otherwise, calls may only work when the app is open or running in the background. I would appreciate it if you could confirm my understanding and advise me on the steps or requirements for obtaining the appropriate permissions. Currently, when I try to launch the app in XCode, I see an error (screenshot).

I'm integrating Twilio Voice (v6.12.1) into my React Native app (using Swift bridging for iOS) and have implemented full VoIP, PushKit, and CallKit support for incoming calls. ✅ What works: Incoming calls trigger the VoIP push and display the full-screen CallKit interface (or fallback UI). Decline Call works as expected. Call logs and events print correctly. ❌ Problem: When I try to accept the call using the CallKit Accept button or React Native fallback UI, I consistently get: ❌ [TwilioVoiceModule] answerCall() callInvite is missing. I also noticed that the console logs for answerCall() are being printed three times in a row, even though the accept button is only pressed once. Additionally in the first time console, answerCall() CallInvite found, accepting... 🔍 Observations: The callInvite is properly received when the VoIP push arrives. But when answerCall() is triggered, callInvite becomes nil. This happens in CallKit accept, RN UI accept, and even notification banner accept. 📦 How it's set up (summarized): PushKit Registration – via PKPushRegistry in AppDelegate.swift VoIP push handling – forwards payload to TwilioVoiceModule.handleIncomingPush() CallKit integration – uses CXProviderDelegate to report and handle accept actions JS Bridge – emits acceptCallAction to JS React Native calls TwilioVoiceModule.answerCall(uuid, callSid) In answerCall() method: self.callInvite is nil – so call cannot be accepted. Attaching the link to view the relevant code: https://docs.google.com/document/d/15pNjKrfk954OaotpMIEh3xQUtst---1K45DBXoYctGM/edit?usp=sharing 💡 Call Accept Flow (iOS): VoIP Push → TwilioVoiceModule.handleIncomingPush() Twilio SDK creates callInvite reportNewIncomingCall() triggers CallKit UI On accept: CXAnswerCallAction → emits event to JS RN calls TwilioVoiceModule.answerCall(uuid, callSid) Problem: callInvite is already nil ❓ What I'm trying to understand: Why is callInvite becoming nil before answerCall() is called? Why are the logs showing the answerCall() call 3 times? Is there a race condition or multiple accept triggers? Should I ensure callInvite is accepted only once across all 3 accept paths? ** 💬 Any help would be appreciated.** 📱 Environment: React Native 0.78.x iOS 17+ Swift bridging with TwilioVoiceModule.swift Twilio Voice SDK 6.12.1 PushKit + CallKit + react-native-callkeep

We are observing unexpected behavior in Apple Push Notification Service (APNS) delivery and would appreciate clarification and guidance. Below is a detailed breakdown of the scenario and related questions. Abbreviations: APNP – Apple Push Notification Provider APNS – Apple Push Notification Service Scenario: User1 is registered on iOS device1. Flight Mode is enabled on iOS device1. User2 initiates a call to User1 (Time t = 0 sec). User2 cancels the outgoing call after 5 seconds (Time t = 5 sec). Flight Mode is disabled on iOS device1 after 20 seconds (Time t = 25 sec). Observation: iOS device1 displays an incoming call notification (CallKit UI) after flight mode is turned off, despite the call being cancelled by User2. This notification disappears automatically after approximately 8–10 seconds. Logic Flow: At time t = 0, our APNP sends a VoIP push (priority) to APNS for the incoming call. Since device1 is in flight mode, APNS cannot deliver the push. At t = 25 sec, after flight mode is turned off, APNS delivers the cached VoIP push to device1. The app takes ~5 seconds to initialize (CSDK setup, SIP registration, etc.). It eventually receives a SIP NOTIFY with state="full" and empty dialog info (indicating no active call). Consequently, the CallKit incoming call is removed after ~8 seconds. Questions: → We set the apns-expiration header to 0, expecting that the VoIP push would not be delivered if the device was unreachable when the push was sent. However, APNS still delivers the push 20–30 seconds later, once the device is back online. Q. Why is the apns-expiration header not respected in this case? → Upon receiving the VoIP push, we require ~10–12 seconds to determine if a visible CallKit notification is still relevant (e.g., by completing SIP registration and checking for active dialogs). Q. Is it acceptable, per Apple guidelines, to intentionally delay showing the CallKit UI (incoming call) for 10–15 seconds after receiving the VoIP push? → Apple documentation states that the priority VoIP push channel should be used only for notifying incoming calls, while regular (non-VoIP) pushes should be used for other updates, including call cancellations. Q. What is the rationale behind discouraging the use of the priority VoIP push channel for call cancellation events? In some cases, immediate cancellation notification is as critical as the initial incoming call. Would Apple consider it acceptable to occasionally use the priority VoIP channel for rare call-cancellation scenarios without risking throttling or suspension? → In our implementation, we send an incoming call notification via the priority VoIP channel. Shortly after, we send a call cancellation notification on the regular push channel, marked with "content-available": 1. We expect this regular push to wake the app (triggering application:didReceiveRemoteNotification:fetchCompletionHandler:), but in practice the app never wakes, and our debug logs inside that delegate method never appear. Q. Under what exact conditions does a "content-available": 1 regular push fail to wake the app when it follows a VoIP push? Are there additional requirements (e.g., background modes, rate limits, power optimizations) that could prevent the delegate from being called? → According to Apple documentation: “APNs stores only one notification per bundle ID. When multiple notifications are sent to the same device for the same bundle ID, APNs keeps only the latest one.” However, in our tests: If a device is offline when APNs receives both: (a) a priority VoIP push for an incoming call, (b) a regular push for call cancellation (same bundle ID), Upon the device reconnecting, APNs still delivers the earlier VoIP push, instead of discarding it and delivering only the most recent (cancellation) notification. Q. Why doesn’t APNs replace the queued VoIP push with the newer regular push when both share the same bundle ID? Is this expected behavior due to channel type differences (VoIP vs. regular), or is there a way to ensure that the latest notification (even if regular) supersedes the earlier VoIP push? We’d appreciate your input or recommendations on handling such delayed pushes and any best practices for VoIP push expiration handling and call UI timing.