We are facing a DNS resolution issue with a specific ISP, where our domain name does not resolve correctly using the system DNS. However, the same domain works as expected when a custom DNS resolver is used.
On Android, this is straightforward to handle by configuring a custom DNS implementation using OkHttp / Retrofit. I am trying to implement a functionally equivalent solution in native iOS (Swift / SwiftUI).
Android Reference (Working Behavior) :
val dns = DnsOverHttps.Builder()
.client(OkHttpClient())
.url("https://cloudflare-dns.com/dns-query".toHttpUrl())
.bootstrapDnsHosts(InetAddress.getByName("1.1.1.1"))
.build()
OkHttpClient.Builder()
.dns(dns)
.build()
Attempted iOS Approach
I attempted the following approach :
Resolve the domain to an IP address programmatically (using DNS over HTTPS)
Connect directly to the resolved IP address
Set the original domain in the Host HTTP header
DNS Resolution via DoH :
func resolveDomain(domain: String) async throws -> String {
guard let url = URL(
string: "https://cloudflare-dns.com/dns-query?name=\(domain)&type=A"
) else {
throw URLError(.badURL)
}
var request = URLRequest(url: url)
request.setValue("application/dns-json", forHTTPHeaderField: "accept")
let (data, _) = try await URLSession.shared.data(for: request)
let response = try JSONDecoder().decode(DNSResponse.self, from: data)
guard let ip = response.Answer?.first?.data else {
throw URLError(.cannotFindHost)
}
return ip
}
API Call Using Resolved IP :
func callAPIUsingCustomDNS() async throws {
let ip = try await resolveDomain(domain: "example.com")
guard let url = URL(string: "https://(ip)") else {
throw URLError(.badURL)
}
let configuration = URLSessionConfiguration.ephemeral
let session = URLSession(
configuration: configuration,
delegate: CustomURLSessionDelegate(originalHost: "example.com"),
delegateQueue: .main
)
var request = URLRequest(url: url)
request.setValue("example.com", forHTTPHeaderField: "Host")
let (_, response) = try await session.data(for: request)
print("Success: (response)")
}
Problem Encountered
When connecting via the IP address, the TLS handshake fails with the following error:
Error Domain=NSURLErrorDomain Code=-1200
"A TLS error caused the secure connection to fail."
This appears to happen because iOS sends the IP address as the Server Name Indication (SNI) during the TLS handshake, while the server’s certificate is issued for the domain name.
Custom URLSessionDelegate Attempt :
class CustomURLSessionDelegate: NSObject, URLSessionDelegate {
let originalHost: String
init(originalHost: String) {
self.originalHost = originalHost
}
func urlSession(
_ session: URLSession,
didReceive challenge: URLAuthenticationChallenge,
completionHandler: @escaping (URLSession.AuthChallengeDisposition, URLCredential?) -> Void
) {
guard challenge.protectionSpace.authenticationMethod == NSURLAuthenticationMethodServerTrust,
let serverTrust = challenge.protectionSpace.serverTrust else {
completionHandler(.performDefaultHandling, nil)
return
}
let sslPolicy = SecPolicyCreateSSL(true, originalHost as CFString)
let basicPolicy = SecPolicyCreateBasicX509()
SecTrustSetPolicies(serverTrust, [sslPolicy, basicPolicy] as CFArray)
var error: CFError?
if SecTrustEvaluateWithError(serverTrust, &error) {
completionHandler(.useCredential, URLCredential(trust: serverTrust))
} else {
completionHandler(.cancelAuthenticationChallenge, nil)
}
}
}
However, TLS validation still fails because the SNI remains the IP address, not the domain.
I would appreciate guidance on the supported and App Store–compliant way to handle ISP-specific DNS resolution issues on iOS. If custom DNS or SNI configuration is not supported, what alternative architectural approaches are recommended by Apple?
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I would like to inquire about Apple's recommended best practices for iPhone thermal management. Specifically, what actions are developers expected to take to prevent the device from overheating?
I am aware that we should subscribe to Thermal State Notifications and throttle performance accordingly—such as by reducing streaming quality or temporarily disabling active features. Beyond these measures, are there any other strategies you recommend to mitigate thermal issues and help the device cool down?
From watching the video on App Attest the answer would appear to be no, but the video is a few years old so in hope, I thought I would post this question anyway.
There's several scenarios where I would like a notification service extension to be able to use App Attest in communications with the back end(for example to send a receipt to the backend acknowledging receipt of the push, fetching an image from a url in the push payload, a few others).
Any change App Attest can be used in by a notification service extension?
I'm using a custom modifier called AutoSheetDetentModifier to automatically size a sheet based on its content.
On iOS 26, it works as expected: the content height is measured correctly and the sheet shrinks to match that height.
However, on iOS 16, 17 and 18, the same code doesn’t work. The content height is still measured, but the sheet does not reduce its height. Instead, the sheet remains larger and the content appears vertically centered. (Note that content() includes ScrollView)
public struct AutoSheetDetentModifier: ViewModifier {
@State private var height: CGFloat = 380 // default value to avoid bouncing
public func body(content: Content) -> some View {
content
.modifier(MeasureHeightViewModifier(height: $height))
.presentationDetents([.height(height)])
}
}
public struct MeasureHeightViewModifier: ViewModifier {
@Binding var height: CGFloat
public func body(content: Content) -> some View {
content
.fixedSize(horizontal: false, vertical: true)
.background(
GeometryReader { geo -> Color in
DispatchQueue.main.async {
height = geo.size.height
}
return Color.clear
}
)
}
}
extension View {
public func applyAutoSheetDetent() -> some View {
self
.modifier(AutoSheetDetentModifier())
}
}
public var body: some View {
VStack {
header()
content() // includes ScrollView
footer()
}
.background(Color.customGray)
.applyAutoSheetDetent()
}
func content() -> some View {
ScrollView {
VStack {
ForEach(items) { item in
itemRow(item)
}
}
}
.frame(maxHeight: UIScreen.main.bounds.height * 0.7)
}
Screenshot from iOS 26 (working as expected):
Screenshot from iOS 18 (not working):
How can I make .presentationDetents(.height) shrink the sheet correctly on iOS 16–18, the same way it does on iOS 26?
90714: Invalid binary. The app contains one or more corrupted binaries. Please rebuild the app and resubmit.
我开发的OC项目,三个月前打包分发还没有问题,半个月前开始就一直报这个错。查了很多资料都无法解决,所有的SDK也都升级了,还是报这个错,麻烦Apple的工程师帮忙指正一下问题,如何解决这个问题。
Topic:
Developer Tools & Services
SubTopic:
Xcode
Tags:
iOS
App Store Connect
TestFlight
Developer Program
I'm getting the following error when I try to make a dev build for iOS even though I am an admin:
✖ Failed to register bundle identifier
Apple 403 detected - Access forbidden.
This request is forbidden for security reasons - You currently don't have access to this membership resource.
Not certain how to proceed from here
Device: iPhone 17 Series
System: iOS 26.0.0
Wi-Fi: TKIP encryption protocol
Question: Unable to join the network
We have several products that are used by connecting to iPhone via Wi-Fi.
Recently, many customers who have purchased the iPhone 17 series have reported that they are unable to connect to Wi-Fi.
For Wi-Fi with TKIP encryption, after entering the password correctly to connect to the Wi-Fi, a pop-up appears stating "Unable to join the network.".
Only Wi-Fi with WPA2-AES can be used normally.
Before that, during the iPhone 11 era or even earlier, the TKIP encryption method was in normal use. However, the new iPhone models were incompatible with it, which obviously caused great inconvenience.
I hope the engineers can fix this issue to support Wi-Fi with older encryption protocols.
I'm trying to sync authentication data from my iOS app to a Safari Web Extension using App Groups, but the extension isn't consistently receiving the data.
Setup:
App Group: group.com.airaai.AiraApp (configured in both app and extension)
iOS app writes auth data using UserDefaults(suiteName: "group.com.airaai.AiraApp")
Extension's Swift SafariWebExtensionHandler reads from App Groups in beginRequest()
Extension's JavaScript reads from browser.storage.local
Problem:
Extension popup always shows "logged out" even when:
User is logged into main iOS app
Auth data exists in App Groups (verified via native module logs)
Handler successfully writes test values to extension storage
Current Behavior:
Handler CAN read from App Groups ✅
Handler CAN write test values to extension storage ✅
But auth data doesn't appear in browser.storage.local when popup checks ❌
Popup reads empty keys even though handler logged writing them
Code:
// Handler reads from App Groups
guard let sharedDefaults = UserDefaults(suiteName: "groupName") else { return }
let authData = sharedDefaults.string(forKey: "auth_data")
// Handler writes to extension storage (tried multiple suite names)
let extensionDefaults = UserDefaults(suiteName: Bundle.main.bundleIdentifier ?? "")
extensionDefaults?.set(authData, forKey: "oauth_token")
extensionDefaults?.synchronize()
// Popup reads from storage
browser.storage.local.get(['oauth_token']).then(data => {
console.log(data); // Always empty {}
});
What I've tried:
✅ App Groups properly configured in both targets
✅ Extension has App Groups capability enabled
✅ Multiple UserDefaults suite names (bundle ID, bundle ID + suffix)
✅ Delayed sync attempts in handler
✅ Comprehensive logging
Questions:
What is the correct UserDefaults suite name for Safari extension storage on iOS?
When does beginRequest() get called? Can it be triggered manually?
Is App Groups the right approach, or should I use a different pattern?
Alternatives I've considered:
Deep link/redirect method (app opens Safari with token in URL)
Content script intercepts URL and sends to background script
Is this a supported approach for iOS Safari extensions?
Any guidance or examples would be greatly appreciated!
Hello everyone! I'm a newly graduated Computer Engineer living in Türkiye. I've been developing my skills in the iOS field for a while now. But sometimes I get lost and don't know what to do. I've just joined this community and have a request for you. I'd be very grateful if you could share your own advice, experiences you've had along the way, and how you successfully overcame them. I'm open to all kinds of positive or negative feedback. Self-improvement is paramount to me.
We're seeing sporadic crashes on devices running iOS 18.1 - both beta and release builds (22B83). The stack trace is always identical, a snippet of it below. As you can tell from the trace, it's happening in places we embed SwiftUI into UIKit via UIHostingController.
Anyone else seeing this?
4 libobjc.A.dylib 0xbe2c _objc_fatalv(unsigned long long, unsigned long long, char const*, char*) + 30
5 libobjc.A.dylib 0xb040 weak_register_no_lock + 396
6 libobjc.A.dylib 0xac50 objc_storeWeak + 472
7 libswiftCore.dylib 0x43ac34 swift_unknownObjectWeakAssign + 24
8 SwiftUI 0xeb74c8 _UIHostingView.base.getter + 160
9 SwiftUI 0x92124 _UIHostingView.layoutSubviews() + 112
10 SwiftUI 0x47860 @objc _UIHostingView.layoutSubviews() + 36
In Xcode's (version 16.1) "Devices and Simulators" window pressing the device's context menu item "Show Provisioning Profiles..." does nothing: no new window, no message, nothing. How can I fix this?
Topic:
Code Signing
SubTopic:
Certificates, Identifiers & Profiles
Tags:
iOS
Xcode
Provisioning Profiles
From https://developer.apple.com/forums/thread/803945?answerId=862153022#862153022, the testing of Age Range API was not available through xcode simulator back in Oct 2025.
Is this available now? In particular:
Is requestAgeRange testing available through simulator?
Is requestAgeRange testing with sandbox account available through simulator?
Is isEligibleForAgeFeatures available through simulator?
Is isEligibleForAgeFeatures testing with sandbox account available through simulator?
If the answer is "yes" to any of the above, which version of the xcode and ios version should I use?
So far I didn't get any of the above working on the simulator, and I can't find any documentation on the answers above.
Thank you!
I have a FORD F250 2021. I returned for a deployment, and CarPlay does not work in my vehicle. I have tried all the YouTube, TikTok, Facebook, and Instagram videos I could find. They all actually started to repeat, so I decided to come here. My wife has an iPhone 16 Pro Max, and it connects to CarPlay without any issues. Other than all the social media suggestions, do you have any other suggestions? No, I am not ready to purchase a new device.
Our iOS app supports CarPlay capability with the Driving task.
The app is also configured to wake in the background on geofence entry or exit events, even from a terminated (killed) state.
We would like to understand how to detect whether CarPlay is connected to the iPhone when the app wakes up or runs in the background.
In this case, the CarPlay app is not actively running in the Car infotainment system foreground.
Requirement:
The app should perform a background task only when CarPlay is connected, including when launched in the background or from a killed state due to a geofence trigger.
Could you please advise on the recommended way or API to determine CarPlay connection status in this background scenario?
Thanks for the support!
Since updating to Tahoe and Xcode 26 I have found that the UISplitViewController.showDetailViewController() is not working in the iPhone version of my app (it is a universal app). I'm just trying to show a detail view after a tap on a UITableView item. The iPad versions are all working correctly. Has anyone else experienced this or have any advice about what may have changed?
Thanks in advance.
We are facing an issue: push notifications are not being received. We are using the Marketing Cloud SDK for push notifications.
On install, the app correctly registers for push notifications. We pass the required information to Marketing Cloud — for example, contact key, token, etc. Marketing Cloud also confirms that the configuration is set up, and we have tried sending push notifications with proper delivery settings.
The issue is that after some time, the device gets automatically opted out in the Marketing Cloud portal. When we consulted their team, they said this is caused by the “DeviceTokenNotForTopic” error received from APNs. I have verified the certificates and bundle ID from my end — everything looks correct.
Device: iPhone 15, iPhone 17
iOS: 18.7.2, 26.1
Hello, maybe anyone know anything about HCE (Host card emulation) feature on iOS?
As far as I read, it's not possible to achieve this functionality on iOS, but maybe there are plans to implement that? Or maybe it's clear that it wont be allowed to be used at all? Thanks:)
I have been experimenting with the BGContinuedProcessingTask API recently (and published sample code for it https://github.com/infinitepower18/BGContinuedProcessingTaskDemo)
I have noticed that if I lock the phone, the code that runs as part of the task stops executing. My sample code simply updates the progress each second until it gets to 100, so it should be completed in 1 minute 40 seconds. However, after locking the phone and checking the lock screen a few seconds later the progress indicator was in the same position as before I locked it.
If I leave the phone locked for several minutes and check the lock screen the live activity says "Task failed".
I haven't seen anything in the documentation regarding execution of tasks while the phone is locked. So I'm a bit confused if I encountered an iOS bug here?
The Paste button (using UIPasteControll) located on UINavigationBar is not shown at application startup on iOS/iPadOS 26.
This issue will disappear when device is rotated or window size is changed.
And this issue does not occur on iOS / iPadOS 18 and earlier.
I uploaded the sample project to github at the following URL. https://github.com/gpn-galapagos/PasteButtonApp.git
Has anyone had the same issue or knows a workaround?
After the iOS 26 update, unwanted animations appear on UIButton.
I'm using the attributedTitle property of UIButton.Configuration to change the button's text, and an animation appears after iOS 26.
(It's unclear whether it's after iOS 26.0 or iOS 26.1, but it likely started with 26.1.)
The peculiar thing is that the animation only starts appearing on buttons that have been pressed once.
I tried using UIView.performWithoutAnimation and CATransaction's begin(), setDisableActions(true), commit(), but it didn't work.
How should I solve this?
Below is the code for changing the button's text.
func updateTitle() {
let keys = type.keys
if keys.count == 1 {
guard let key = keys.first else { return }
if key.count == 1 {
if Character(key).isLowercase {
self.configuration?.attributedTitle = AttributedString(key, attributes: AttributeContainer([.font: UIFont.systemFont(ofSize: 24, weight: .regular), .foregroundColor: UIColor.label]))
} else if Character(key).isUppercase {
self.configuration?.attributedTitle = AttributedString(key, attributes: AttributeContainer([.font: UIFont.systemFont(ofSize: 22, weight: .regular), .foregroundColor: UIColor.label]))
} else {
self.configuration?.attributedTitle = AttributedString(key, attributes: AttributeContainer([.font: UIFont.systemFont(ofSize: 22, weight: .regular), .foregroundColor: UIColor.label]))
}
} else {
self.configuration?.attributedTitle = AttributedString(key, attributes: AttributeContainer([.font: UIFont.systemFont(ofSize: 18, weight: .regular), .foregroundColor: UIColor.label]))
}
} else {
let joined = keys.joined(separator: "")
self.configuration?.attributedTitle = AttributedString(joined, attributes: AttributeContainer([.font: UIFont.systemFont(ofSize: 22, weight: .regular), .foregroundColor: UIColor.label]))
}
}