February 2023 Summaries

Apple’s deprecation of Game Center’s GKPlayer.playerID property requires Firebase Authentication developers using Game Center Sign-In to transition to the privacy-focused gamePlayerID and teamPlayerID identifiers. Updated Firebase client SDKs will automatically use the new flow and migrate users to gamePlayerID as the primary identifier, with ProviderUserInfo.federatedId returning gamePlayerID instead of playerID. Developers using the REST API must submit playerId along with teamPlayerID and gamePlayerID to signInWithGameCenter; requests using only playerId remain accepted but cannot identify users already migrated through the new SDK. Updated SDKs and REST API support were expected in early February 2023, and migration from playerID to the new identifier format is irreversible.