Interface MobileSessionState

Set while the app is in its cold-start window; requests created in this window carry the app_start_tag analytics tag.

App process start clock in milliseconds, captured when the cold-start window opens. Requests that report the app-start clock (x-ig-app-start-time, the 448 feed/reels_tray) read it from here.

Bandwidth estimator state, accumulated from completed transfers. Absent until the first response; rendered through bandwidthHeaders.

Response when challenge data was purposefully fetched from the checkpoint URL. Set by challenge.route().

Response when a request got a checkpoint error (challenge_required). Set automatically by the error router.

Random lifetime in ms for clientSessionId rotation (20min–24h). Generated once per device.

Whether the app has bound the device family id to its FX/switcher session. Absent (false) while the switcher still probes with an empty family_device_id (FxIgXavSwitcherBadgingDataQuery); set by BindFamilyDeviceId at the point the capture flips (the first two post-login probes send "", the later ones the device family id).

Legacy serialized nav chain carried over from pre-Effect snapshots. Never rendered; the wire x-ig-nav-chain comes from navigation.

App navigation state (screen in front + session back stack), changed by the navigation events below and rendered by the platform header layer. See mobile.navigation.ts.

Random lifetime in ms for pigeonSessionId rotation (20min–24h). Generated once per device.

Routing-map (RMD) state reported on every request once the app has started evaluating its routing map. Absent until then.

Set while the app is running the jobs it launches at user-session creation (see RequestScope's session-start). Requests issued in this window omit the x-pigeon-session-id header: the 448 capture carries it on the pre-login and late-session families but not on the post-login session-start burst (sequences 23–35), where it reappears from the request after the burst.

Pre-computed x-meta-usdid HTTP header value, reused byte-identical on every request until the next USDID re-register. Filled by postUsdidRegistration after a successful mutation, so the registration request itself carries no header on a fresh install (only a value cached from an earlier accepted registration is ever sent). Not persisted across processes by default (the signature embeds a timestamp).

Set once the app has started its zero-rating campaign evaluation; the zero-http-network-interface header is reported from then on. A separate concept from MobileSessionState.rmd: the 448 capture carries x-fb-rmd already on the Loom config request but the network interface only from the zero-campaign request that follows it (see StartZeroInterface).

Zero-rating phase of the session. Absent (older snapshots) means authenticated when authorization is set and logged-out otherwise; read it through zeroPhaseOf.