How to Build Expo Router Auth Guards That Handle Expired Sessions and Deep Links

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Many Expo apps implement basic sign-in correctly but fail to handle edge cases like expired sessions, deep links, and cold-start token refresh in production. A common mistake is placing authentication checks inside individual screens, which risks unprotected routes and brief flashes of incorrect UI before redirects fire. Expo Router's layout-level protected routes offer a more reliable approach, wrapping entire route groups under a single guard that re-evaluates whenever the session state changes. Because session restoration from secure storage is asynchronous, developers must track a loading state and keep the splash screen visible until the storage read completes, preventing premature redirects to sign-in. Handling these four production scenarios — group-level guarding, pre-render session restore, deep-link redirection, and token-refresh races — can significantly improve authentication reliability in Expo apps.

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