Create apps that allow players to interact with each other using GameKit.

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Matchmaking issue on tvOS with GKMatchmakerViewController.Request
Hello ! We are working on a real-time 2-player online game targeting multiple Apple devices. The following issue only occurs on tvOS: When selecting matchmaking to connect with another random player, the native Game Center interface opens and begins the matchmaking process. Almost immediately after clicking "start", the following log appears in the console, and the matchmaking screen remains indefinitely without completing: Timeout while starting matching with request: <GKMatchRequestInternal 0x30d62f690> { defaultNumberOfPlayers : 0 isLateJoin : 0 localPlayerID : U:bea182d69b85f0839e3958742fbc4609 matchType : 0 maxPlayers : 2 minPlayers : 2 playerAttributes : 4294967295 playerGroup : 1 preloadedMatch : 0 recipientPlayerIDs : <__NSArrayM 0x3034ed5c0> {} recipients : <__NSArrayM 0x3034ee280> {} restrictToAutomatch : 0 version : 1 archivedSharePlayInviteeTokensFromProgrammaticInvite, inviteMessage, localizableInviteMessage, messagesBasedRecipients, properties, queueName, recipientProperties, rid, sessionToken : (null) } . Error: (null) However, as shown in the code snippet below, the task does not complete when the log appears. But when we manually cancel the matchmaking process, the "User cancel" log is correctly triggered. var gkMatchRequest = GKMatchRequest.Init(); gkMatchRequest.MinPlayers = 2; gkMatchRequest.MaxPlayers = 2; var matchRequestTask = GKMatchmakerViewController.Request(gkMatchRequest); matchRequestTask.ContinueWith(t => { Debug.LogException(t.Exception); }, TaskContinuationOptions.OnlyOnFaulted); matchRequestTask.ContinueWith(t => { Debug.Log("User cancel"); }, TaskContinuationOptions.OnlyOnCanceled); matchRequestTask.ContinueWith(t => { Debug.Log("Success"); }, TaskContinuationOptions.OnlyOnRanToCompletion); We have tested this on multiple Apple TV and network types (Wi-Fi, 5G, Ethernet), but we consistently encounter this bug along with the same log message. Could you please help us understand or resolve this issue? Thank you.
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109
Apr ’25
GameKit Configuration File - Apple Documentation out of Date
This is the first time I have tried adding achievements to my games. The online documentation says: "Before you can access achievements in your code, you can configure them in Xcode and sync the configuration updates you make with App Store Connect. Begin configuring achievements by creating a GameKit configuration file. In Xcode, choose File > New > File from Template. Select GameKit File, and click Next. In the sheet that appears, enter a name for the configuration and click Create." Sounds easy - except Xcode 16.2 does not have a GameKit File as one of the Templates. Please advise on how to proceed and it would be nice if the documentation were updated.
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91
May ’25
Gamekit Achievements Won't Unhide
Added achievements to my approved app. Added them for the next release version, which I am running in simulator. When I look at the Achievements page, I can see that there are 17 Achievements available (correct), but they all show as hidden, despite checking the "No" box in App Store Connect.
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May ’25
How to Apple Unity Plugins
When running my game in the Unity Editor on Windows platform I get an error: DllNotFoundException: GameKitWrapper assembly:<unknown assembly> type:<unknown type> member:(null) Apple.GameKit.DefaultNSErrorHandler.Init () (at ./Library/PackageCache/com.apple.unityplugin.gamekit@0abcad546f73/Source/DefaultHandlers.cs:35) This is because GameKitWrapper dynamically linked library is not available under Windows platform. Besides, "Apple Build Settings" are declared under UNITY_EDITOR_OSX and also not available under Windows platform. Does anyone managed to solve this?
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318
Jul ’25
How to verify with the appropriate signing authority that Apple signed the public key
Hello I trying to implement authentication via apple services in unity game with server made as another unity app On client side I succesfully got teamPlayerID signature salt timestamp publicKeyUrl According to this documentation https://developer.apple.com/documentation/gamekit/gklocalplayer/fetchitems(foridentityverificationsignature:)?language=objc I have to Verify with the appropriate signing authority that Apple signed the public key. As I said my server is special build of unity project So now I have this kind of C# programm to check apple authority over public certificate i got from publicKeyUrl TextAsset textAsset; byte[] bytes; textAsset = Resources.Load&lt;TextAsset&gt;("AppleRootCA-G3"); bytes = textAsset.bytes; rootCert.ChainPolicy.ExtraStore.Add(new X509Certificate2(bytes)); textAsset = Resources.Load&lt;TextAsset&gt;("AppleRootCA-G2"); bytes = textAsset.bytes; rootCert.ChainPolicy.ExtraStore.Add(new X509Certificate2(bytes)); textAsset = Resources.Load&lt;TextAsset&gt;("AppleIncRootCertificate"); bytes = textAsset.bytes; rootCert.ChainPolicy.ExtraStore.Add(new X509Certificate2(bytes)); rootCert.Build(cert); Where cert is X509Certificate2 object I ge from publicKeyUrl AppleIncRootCertificate AppleRootCA-G2 AppleRootCA-G3 is certificates I got from https://www.apple.com/certificateauthority/ But it is not work Anytime rootCert.Build(cert); return false Why it is not work? May be I build keychain using wrong root CA cert? Or whole approach incorrect? Please help
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80
Jun ’25
Monthly recurring leaderboard and placement achievement?
I would like a monthly recurring leaderboard, but the most days one can set for the recurring leaderboard is 30, and some months have 31 days (or 28/29). This is dumb. I guess I have to manually reset a classic leaderboard each month to get this result? Additionally once it closes and is about to reset (I also have daily recurring leaderboards), I'd like to grant the top placers on the leaderboard a corresponding achievement, but I don't see any way of doing this. I believe I can do all these things on PlayFab, but it'll take a bit more work, and eventually cost. Any one have advise?
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GKLeaderboard.LoadLeaderboards() return empty when testing on Xcode with local gamekit file (Unity)
var allLeaderboards = await GKLeaderboard.LoadLeaderboards(); Log(allLeaderboards.Count); // returns 0 What am I missing?? What doesn’t work: await GKGameActivityDefinition.LoadGameActivityDefinitions() → count = 0 await GKLeaderboard.LoadLeaderboards() (no args) → 0 leaderboards await GKLeaderboard.LoadLeaderboards("MY ID") → returns 0 GkGameActivity.SetScoreOnLeaderboard(Leaderboard, score, context); returns an error since my Leaderboard is null. Activities and leaderboards are defined in GameCenterResources.gamekit in Xcode. Achievements that I add locally in the .gamekit file do not appear at runtime either; only ASC live ones show. ** What works:** xcode- debug- Gamekit- Manage Game progress- I can submit new scores with the plus button and see the notification on my device. await GKLocalPlayer.Authenticate() succeeds. await GKAchievement.LoadAchievements() returns the list of achievements configured in App Store Connect- but not any new local achievements created in Xcode in GameCenterResources.gamekit Environment Device/OS: iPhone on iOS 26.0 beta (Game Center sandbox) Xcode: 26.0 beta 6 Unity: 2022.3.21 Apple GameKit Unity plugin: 2025-beta1 (GameKit package) Signing: Game Center capability enabled; using development provisioning profile GameKit resources: GameCenterResources.gamekit in project (Target: Unity-iPhone), appears under Build Phases → Copy Bundle Resources
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Unity GameKit Plugin w/ Matchmaking Queue is not working
TLDR; I can't get QueueName to work with matchmaking a turn-based match in Unity using matchmaking rules. Long version: I'm using the apple unity plugin found here: https://github.com/apple/unityplugins/blob/main/plug-ins/Apple.GameKit/Apple.GameKit_Unity/Assets/Apple.GameKit/Documentation~/Apple.GameKit.md I have created a Queue, RuleSet and a simple Rule to match players by following these docs tightly: https://developer.apple.com/documentation/gamekit/finding-players-using-matchmaking-rules. Here is the single rule I have that drives matchmaking: { "data" : { "type" : "gameCenterMatchmakingRules", "id" : "[hiddden-rule-id]", "attributes" : { "referenceName" : "ComplimentaryFactionPreference", "description" : "default desc", "type" : "MATCH", "expression" : "requests[0].properties.preference != requests[1].properties.preference", "weight" : null }, "links" : { "self" : "https://api.appstoreconnect.apple.com/v1/gameCenterMatchmakingRules/[hidden-rule-id]" } }, "links" : { "self" : "https://api.appstoreconnect.apple.com/v1/gameCenterMatchmakingRules" } } which belongs to a rule set which belongs to a queue. I have verified these are setup and linked via the App Store Connect API. Additionally, when I tested queue-based matchmaking without a queue established, I got an error in Unity. Now, with this, I do not. However there is a problem when I attempt to use the queue for matchmaking. I have the basic C# function here: public override void StartSearch(NSMutableDictionary<NSString, NSObject> properties) { if (searching) return; base.StartSearch(properties); //Establish matchmaking requests _matchRequest = GKMatchRequest.Init(); _matchRequest.QueueName = _PreferencesToQueue(GetSerializedPreferences()); _matchRequest.Properties = properties; _matchRequest.MaxPlayers = PLAYERS_COUNT; _matchRequest.MinPlayers = PLAYERS_COUNT; _matchTask = GKTurnBasedMatch.Find(_matchRequest); } The _PreferencesToQueue(GetSerializedPreferences()); returns the exact name of the queue I added my ruleset to. After this function is called, I poll the task generated from the .Find(...) function. Every time I run this function, a new match is created almost instantly. No two players are ever added to the same match. Further, I'm running two built game instances, one on a mac and another on an ipad and when I simultaneously test, I am unable to join games this way. Can someone help me debug why I cannot seem to match make when using a queue based approach?
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How to use Unity Apple GameKit Plugin For Rule-based matchmaking?
Hello, **I'm Using ** Unity 6 LTS Unity Apple GameKit + Core plugins Turn-based matchmaking interface w/ 2 players max App Store Connect API for rule-based matchmaking I have already enabled game center in app store connect (I think) authenticated players and matched via friend request I am stuck Using queues to match players automatically I'm working on a rule-based matchmaking system which aims to place two players against each other into a GKTurnBasedMatch. I have a simple Unity Project that correctly authenticates a user and proceeds to send a matchmaking request. The matchmaking script utilizes the Unity plugins' GKTurnBasedMatchmakerViewController.Request(...) request function with a GKMatchRequest.Init() request configured with a QueueName equal to the App Store Connect API Queue I created. The queue I created is also linked to a ruleset with a very basic rule that checks if the properties contains a key called 'preference' that contains a string value for what side the player wants to play for this match. If during the matchmaking, the preferences between players are different, then the match is made and both players should join the match; each player gets to play the side they have chosen. I have my rule expression designed to just check if the preferences are not equal: requests[0].properties.faction_preference != requests[1].properties.faction_preference When I launch the game with two physical iPads and begin the matchmaking request, each player is immediately presented with two options: Invite a friend, or Start game The Problem: Inviting a friend works to get two players into a game, but queue seems to not matter, and clicking start game will just put the current player into its own match (no one joins). The Question: How do I get queue based matchmaking to work in Unity for a Turn-based match with only two players who are able to select the enemy side they want to play dictated by a rule that compares enemy play-side preferences? Resources I've used: Apple Unity GameKit Plugin: https://github.com/apple/unityplugins Matchmaking: https://developer.apple.com/documentation/gamekit/matchmaking-rules Multiplayer rulesets: https://developer.apple.com/documentation/gamekit/finding-players-using-matchmaking-rules
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Unity GameCenter Leaderboard issue
Hey, i have created a game in unity with the apple core and apple gamekit plugins present. I setup 5 leaderboards on the app store connect. I made a unity build and did the whole testflight build loop to test everything. When i open my gamecenter panel via the button i see my leaderboards but they show as MISSING TITLE which is weird because i have for sure set them up correctly they have a leaderboard reference name and leaderboard id as well. When debugging i can see that when i call my submit score function it gets submitted with no error but then i also dont see the score appear anywhere . Keep in mind the leaderboards are not live and are being tested on testflight first
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1.1k
Jan ’25
GameplayKit usage with Swift 6: Call to main actor-isolated instance method 'run' in a synchronous nonisolated context
Hi there, With a couple of other developers we have been busy with migrating our SpriteKit games and frameworks to Swift 6. There is one issue we are unable to resolve, and this involves the interaction between SpriteKit and GameplayKit. There is a very small demo repo created that clearly demonstrates the issue. It can be found here: https://github.com/AchrafKassioui/GameplayKitExplorer/blob/main/GameplayKitExplorer/Basic.swift The relevant code also pasted here: import SwiftUI import SpriteKit struct BasicView: View { var body: some View { SpriteView(scene: BasicScene()) .ignoresSafeArea() } } #Preview { BasicView() } class BasicScene: SKScene { override func didMove(to view: SKView) { size = view.bounds.size anchorPoint = CGPoint(x: 0.5, y: 0.5) backgroundColor = .gray view.isMultipleTouchEnabled = true let entity = BasicEntity(color: .systemYellow, size: CGSize(width: 100, height: 100)) if let renderComponent = entity.component(ofType: BasicRenderComponent.self) { addChild(renderComponent.sprite) } } } @MainActor class BasicEntity: GKEntity { init(color: SKColor, size: CGSize) { super.init() let renderComponent = BasicRenderComponent(color: color, size: size) addComponent(renderComponent) let animationComponent = BasicAnimationComponent() addComponent(animationComponent) } required init?(coder: NSCoder) { fatalError("init(coder:) has not been implemented") } } @MainActor class BasicRenderComponent: GKComponent { let sprite: SKSpriteNode init(color: SKColor, size: CGSize) { self.sprite = SKSpriteNode(texture: nil, color: color, size: size) super.init() } required init?(coder: NSCoder) { fatalError("init(coder:) has not been implemented") } } class BasicAnimationComponent: GKComponent { let action1 = SKAction.scale(to: 1.3, duration: 0.07) let action2 = SKAction.scale(to: 1, duration: 0.15) override init() { super.init() } override func didAddToEntity() { if let renderComponent = entity?.component(ofType: BasicRenderComponent.self) { renderComponent.sprite.run(SKAction.repeatForever(SKAction.sequence([action1, action2]))) } } required init?(coder: NSCoder) { fatalError("init(coder:) has not been implemented") } } As SKNode is designed to run on the MainActor, the BasicRenderComponent is attributed with MainActor as well. This is needed as this GKComponent is dedicated to encapsulate the node that is rendered to the scene. There is also a BasicAnimationComponent, this GKComponent is responsible for animating the rendered node. Obviously, this is just an example, but when using GameplayKit in combination with SpriteKit it is very common that a GKComponent instance manipulates an SKNode referenced from another GKComponent instance, often done via open func update(deltaTime seconds: TimeInterval) or as in this example, inside didAddToEntity. Now, the problem is that in the above example (but the same goes foupdate(deltaTime seconds: TimeInterval) the methoddidAddToEntity is not isolated to the MainActor, as GKComponent is not either. This leads to the error Call to main actor-isolated instance method 'run' in a synchronous nonisolated context, as indeed the compiler can not infer that didAddToEntity is isolated to the MainActor. Marking BasicAnimationComponent as @MainActor does not help, as this isolation is not propogated back to the superclass inherited methods. In fact, we tried a plethora of other options, but none resolved this issue. How should we proceed with this? As of now, this is really holding us back migrating to Swift 6. Hope someone is able to help out here!
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1.1k
Oct ’24
Crash after using Apply unity plugin (GameKit-3.0.0)
Hi, I tried to save the game progress using the official Apple plugin for Unity but the crash happened when I active the "iCloud Documents" inside capabilities and when deactivated it this error message appeared: Code=27 Domain=GKErrorDomain Description=The requested operation could not be completed because you are not signed in to iCloud or have not enabled iCloud Drive. (UbiquityContainerUnavailable) Authentication with Game Center works fine using the Core plugin, but nothing works correctly when I use the GameKit plugin. Note: I already active iCloud for app Identifier. Tichnecal informations: Unity version: 2022.3.47f1 LTS XCode 16 Swift 6 GameKit-3.0.0 (Apply unity plugin) Core-3.1.5 (Apply unity plugin)
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978
Nov ’24
Editor Ok, but running batch get: Cannot locate a Release or Debug Apple.GameKit native library for macOS
After running build.py -p Core GameKit and adding the tar balls to the Unity project in Assets/ExternalPackages no packages seem to be found when running the build using our continuous integration system. This was not the case when the project was opened in the Editor. It looks like in Apple.Core, the ApplePluginEnvironment hasn't run the OnEditorUpdate function and so the _appleUnityPackages Dictionary is empty. A change to ApplePlugInEnvironment.cs seemed to fix the issue: public static AppleNativeLibrary GetLibrary(string packageDisplayName, string appleBuildConfig, string applePlatform) { // ?FIX?: If we're not in the editor, we might not have updated the package list. if (_appleUnityPackages.Count == 0 && _updateState == UpdateState.Initializing) { OnEditorUpdate(); // UpdateState.Initializing OnEditorUpdate(); // UpdateState.Updating } I'm not sure if this is something we're doing incorrectly, the documentation for the plug-in mostly covered building the package.
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670
Dec ’24
Game Center save game data to iCloud
We are trying to implement saving and fetching data to and from iCloud, but it have some problems. MacOS: 15.3 Here is what I do: Enable Game Center and iCloud capbility in Signing & Capabilities, pick iCloud Documents, create and select a Container. Sample code: void SaveDataToCloud( const void* buffer, unsigned int datasize, const char* name ) { if(!GKLocalPlayer.localPlayer.authenticated) return; NSData* data = [ NSData dataWithBytes:databuffer length:datasize]; NSString* filename = [ NSString stringWithUTF8String:name ]; [[GKLocalPlayer localPlayer] saveGameData:data withName:filename completionHandler:^(GKSavedGame * _Nullable savedGame, NSError * _Nullable){ if (error != nil) { NSLog( @"SaveDataToCloud error:%@", [ error localizedDescription ] ); } }]; } void FetchCloudSavedGameData() { if ( !GKLocalPlayer.localPlayer.authenticated ) return; [ [ GKLocalPlayer localPlayer ] fetchSavedGamesWithCompletionHandler:^(NSArray<GKSavedGame *> * _Nullable savedGames, NSError * _Nullable error) { if ( error == nil ) { for ( GKSavedGame *item in savedGames ) { [ item loadDataWithCompletionHandler:^(NSData * _Nullable data, NSError * _Nullable error) { if ( error == nil ) { //handle data } else { NSLog( @"FetchCloudSavedGameData failed to load iCloud file: %@, error:%@", item.name, [ error localizedDescription ] ); } } ]; } } else { NSLog( @"FetchCloudSavedGameData error:%@", [ error localizedDescription ] ); } } ]; } Both saveGameData and fetchSavedGamesWithCompletionHandler are not reporting any error, when debugging, saveGameData completionHandler got a nil error, and can get a valid "savedGame", but when try to rebot the game and use "fetchSavedGamesWithCompletionHandler" to fetch data, we got nothing, no error reported, and the savedGames got a 0 length. From this page https://developer.apple.com/forums/thread/718541?answerId=825596022#825596022 we try to wait 30sec after authenticated , then try fetchSavedGamesWithCompletionHandler, still got the same error. Checked: Game Center and iCloud are enabled and login with the same account. iCloud have enough space to save. So what's wrong with it.
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561
Mar ’25
How do I test a new leaderboard added to a Published app with prior leaderboard?
Hi I have attempted to find a fix for my issue via documentation online and one phone support ( not code level support ) call to no end. I could continue to try various things but would like to see if someone else has encountered this issue and a fix for it. Background: My Game app is live on App Store and has 1 classic leaderboard . I am now getting ready to submit an update to the app and it also entails adding a new recurring leaderboard. I added the leaderboard in App Store. I however have NOT uploaded my new build yet. I have also not added my leaderboards ( currently live and not live ) to any set. When I try to submit scores using GKLeaderboard.submitScore(_:context:player:leaderboardIDs:completionHandler:) to the new non-live leaderboard it works ( gives me no error ) When I try to load the scores from the new non-live leaderboard GKLeaderboard.loadLeaderboards(IDs:completionHandler:) loadEntries(for:timeScope:range:completionHandler:) it fails. Error: "leaderboardID not found" I could try ( and will ) uploading the new build to AppStore connect and associating the new leaderboard to it before testing again. try associating each leaderboard to a set Is there anything else that I should be aware of ? Thanks in advance
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79
Jul ’25
Matchmaking issue on tvOS with GKMatchmakerViewController
Hello, We are working on a real-time 2-player online game targeting multiple Apple devices. The following issue only occurs on tvOS: When selecting matchmaking to connect with another player, the native Game Center interface opens and begins the matchmaking process. Almost immediately, the following log appears in the console, and the matchmaking screen remains indefinitely without completing: Timeout while starting matching with request: <GKMatchRequestInternal 0x30d62f690> { defaultNumberOfPlayers : 0 isLateJoin : 0 localPlayerID : U:bea182d69b85f0839e3958742fbc4609 matchType : 0 maxPlayers : 2 minPlayers : 2 playerAttributes : 4294967295 playerGroup : 1 preloadedMatch : 0 recipientPlayerIDs : <__NSArrayM 0x3034ed5c0> {} recipients : <__NSArrayM 0x3034ee280> {} restrictToAutomatch : 0 version : 1 archivedSharePlayInviteeTokensFromProgrammaticInvite, inviteMessage, localizableInviteMessage, messagesBasedRecipients, properties, queueName, recipientProperties, rid, sessionToken : (null) } . Error: (null) However, the task does not complete when the log appears (our Debug.Log are nerver called). But if we manually cancel the matchmaking process, the "User cancel" log is correctly triggered. Here is a code snippet for the request : var gkMatchRequest = GKMatchRequest.Init(); gkMatchRequest.MinPlayers = 2; gkMatchRequest.MaxPlayers = 2; var matchRequestTask = GKMatchmakerViewController.Request(gkMatchRequest); matchRequestTask.ContinueWith(t => { Debug.LogException(t.Exception); }, TaskContinuationOptions.OnlyOnFaulted); matchRequestTask.ContinueWith(t => { Debug.LogInfo("User cancel"); }, TaskContinuationOptions.OnlyOnCanceled); matchRequestTask.ContinueWith(t => { Debug.LogInfo("Success"); }, TaskContinuationOptions.OnlyOnRanToCompletion); We have tested this on multiple devices and network types (Wi-Fi, 5G, Ethernet), but we consistently encounter this bug along with the same log message. Could you please help us understand or resolve this issue? Thank you.
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127
Apr ’25
Game Center Authentication Crashing - Unity 6, Gamekit 3.0.2
When testing my development build for gamecenter authentication, the game crashes. I've breadcrumbed it to the "await GKLocalPlayer.Authenticate();" call. Can't find any documentation on this issue and have been looking through the forums! I've already done all of the usual stuff like verifying bundle identifiers match, ensuring game center is enabled for the app, setting up app store connect, using a sandbox account, etc... Please point me to some resources if you know any. Any help is appreciated, I'm starting to lose hope here!
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112
Apr ’25
Testing Achievements - Apple Documentation out of Date
New to achievements. I added them in App Store Connect and want to test them. Apple Documentation says this: "Before you begin testing your GameKit configuration, you need to enable Debug Mode. In Xcode, choose Product > Scheme > Edit Scheme. From the Run configuration, select Options and toggle Enable Debug Mode. To begin testing your achievement configuration, open the game Progress Manager. In Xcode, choose Debug > GameKit > Manage Game Progress." Sounds easy enough, but there is no "GameKit" under Debug in Xcode 16.2.
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99
May ’25
authenticateHandler events not being received on iOS 18
I work on a team that provides an SDK for another game to handle various tasks like authentication. They are experiencing a case where devices using iOS 17 are failing to authenticate with GameCenter, receiving the message "The requested operation could not be completed because local player has not been authenticated." We imagine this is because they still have some setup to finish regarding GameCenter itself, and we're working with them to take care of that. However, on iOS 18, their app ends up waiting indefinitely for GameCenter authentication messages that it never receives. That's where we're puzzled. We expect them to have the same outcome regardless of OS version. We initiate GameCenter authentication by setting an authenticateHandler after some initial application setup. The handler has code to account for UI, errors, and successful authentication. On iOS 17, it's clear that it's getting called as expected because they receive an indication that the player isn't authenticated. But on iOS 18, it looks like the same handler code on iOS 18 isn't being called at all. Are there differences in how iOS 18 interacts with the authenticationHandler that we somehow aren't accounting for? Or is there potentially something else that we're doing incorrectly that is manifesting only on iOS 18? Here's a simplified version of our login function code (in Obj-C++). There is no OS-specific code, and the job that owns this function does stay in scope until after authentication is complete. void beginLogin() { // Snip: Check if the user is already logged in. // Snip: Prevent multiple concurrent calls to this function. auto authenticateHandler = ^(UIViewController* gcViewController, NSError* error) { if (gcViewController != nil) { // Snip: Display the UI } else if (error != nil) { // Snip: Handle the error. } else { if ([[GKLocalPlayer localPlayer] isAuthenticated]) { // Snip: Handle successful authentication. } else { // Snip: Handle other case. } } }; [[GKLocalPlayer localPlayer] setAuthenticateHandler: authenticateHandler]; }
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124
May ’25
Blurry Game Center Achievement Images?
Hey all — I’ve been building out my first set of Game Center Achievements for a game I’m working on, and I’ve run into something odd with the image quality. The specs say to upload icons at 512x512 or 1024x1024@2x. I’ve been uploading 1024x1024 PNGs (without explicitly naming them “@2x” since there’s only one upload slot), assuming that Game Center would just handle the scaling automatically — kind of like how a lot of things are getting more streamlined across platforms lately. But in testing, the icons are showing up a bit blurry, especially in the Game Center interface. It’s not horrible, but it’s definitely softer than I expected — more like low-res than Retina. All my test devices (outside the Simulator) are running iOS 26, so I’m also wondering if this might be a beta-related display bug? Has anyone else run into this? Curious if I’m missing a best practice here, or if I really do need to ensure I’m uploading it with the @2x suffix, or maybe something else entirely? Thanks!
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Jul ’25