--- title: Changes in Game Center Sign-In | daily.dev description: Apple deprecated the playerID property on GKPlayer in favor of teamPlayerID and gamePlayerID for improved player privacy. Firebase Authentication is updating... canonical: https://daily.dev/posts/changes-in-game-center-sign-in-mrmkwdgov twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Changes in Game Center Sign-In | daily.dev og:description: Apple deprecated the playerID property on GKPlayer in favor of teamPlayerID and gamePlayerID for improved player privacy. Firebase Authentication is updating... og:url: https://daily.dev/posts/changes-in-game-center-sign-in-mrmkwdgov og:image: https://api.daily.dev/og/posts/MrMKwDgOv.png og:image:alt: Changes in Game Center Sign-In og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Changes in Game Center Sign-In **[Firebase](https://daily.dev/sources/firebase-blog)** · 2 min read · 0 upvotes · 0 comments ## Summary Apple deprecated the playerID property on GKPlayer in favor of teamPlayerID and gamePlayerID for improved player privacy. Firebase Authentication is updating Game Center Sign-in to use these new fields as the primary user identifier instead of playerID. Developers need to upgrade to the latest Firebase SDK to automatically adopt the new flow; REST API users must include both old and new fields in signInWithGameCenter calls. Migration of user identifiers to the new format is irreversible. Updated client SDKs and REST API were expected in early February 2023. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Why is Apple's GKPlayer playerID deprecated and what should I use instead in Firebase Authentication? Apple deprecated the playerID property of GKPlayer in favor of teamPlayerID and gamePlayerID to increase player privacy. Firebase Authentication is introducing gamePlayerID and teamPlayerID as optional fields that replace playerID as the primary user identifier for Game Center Sign-in once a valid ID is passed, requiring an SDK upgrade to take effect. _Developers migrating Game Center sign-in should track Firebase Authentication changes like this on daily.dev._ ### Do I need to change anything when calling signInWithGameCenter through the Firebase REST API after the Game Center identifier change? Yes, calls should include both the original playerId and the new teamPlayerID and gamePlayerID fields. Calls containing only playerId will not be rejected, but existing users already migrated to the new SDK cannot be identified without the new fields, and the new identifiers appear in the response body and any ID tokens. _Teams maintaining Game Center auth flows can follow REST API migration details like this on daily.dev._ ### Is upgrading Firebase Game Center user identifiers from playerID to gamePlayerID reversible? No, upgrading the user identifier from playerID to the new gamePlayerID/teamPlayerID format is an irreversible process. Once a user is migrated via the updated SDK, they cannot be reverted to using the old playerID-based identification. _Anyone planning an irreversible auth migration can follow updates like this on daily.dev._ ## Similar posts on daily.dev - [Elevating app quality: Reducing memory usage and improving device migration](https://daily.dev/posts/elevating-app-quality-reducing-memory-usage-and-improving-device-migration-y7shb1pqd) · Android Developers Blog · 1 upvotes · 0 comments - [Kotlin / Wasm — Auth part 2: Apple sign in](https://daily.dev/posts/kotlin-wasm-auth-part-2-apple-sign-in-zl0teqgtf) · ProAndroidDev · 0 upvotes · 0 comments --- Tags: [#ios](https://daily.dev/tags/ios), [#authentication](https://daily.dev/tags/authentication), [#firebase](https://daily.dev/tags/firebase) [View this post on daily.dev](https://daily.dev/posts/changes-in-game-center-sign-in-mrmkwdgov) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Changes in Game Center Sign-In","url":"https://daily.dev/posts/changes-in-game-center-sign-in-mrmkwdgov","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/changes-in-game-center-sign-in-mrmkwdgov"},"datePublished":"2026-08-23T12:21:19.176Z","dateModified":"2026-08-23T12:46:35.774Z","description":"Apple deprecated the playerID property on GKPlayer in favor of teamPlayerID and gamePlayerID for improved player privacy. 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