# iOS privacy and ATT (/docs/sdk/app-store-privacy) This page describes the SDK's behavior and controls. It does not prescribe your app's App Store Connect answers: those answers cover your whole app, including the events you send and the destinations you enable. ## ATT and Layers consent are separate [#att-and-layers-consent-are-separate] Starting in SDK **3.3.0**, requesting App Tracking Transparency permission: * the SDK records the current ATT status; * it includes the IDFA only when ATT returns `authorized`; and * in Swift, Flutter, and Unity, it refreshes the IDFV when that identifier is available. By default, the ATT result does **not** call `setConsent` or change Layers analytics or advertising consent. A denied, restricted, or not-determined ATT result leaves the IDFA absent but does not turn off Layers event delivery. Swift keeps the old `attDrivesAdvertisingConsent` configuration option for source compatibility. It is deprecated and defaults to `false`; setting it to `true` preserves the old Swift mirroring behavior. React Native, Expo, Flutter, and Unity do not map ATT onto Layers consent. ## What continues without IDFA [#what-continues-without-idfa] Install attribution, analytics, and configured Conversions API forwarding keep working when IDFA is unavailable. The IDFA is one match signal, not an on/off switch for the pipeline. The SDK and ingest service continue to use the signals that are available, including the per-install ID, IDFV, app user ID after `identify`, deep-link and campaign click identifiers, event data, and request metadata. For Meta, the IDFA is sent as `madid` only when it is present; without it, the payload can still use fields such as the install or app user ID, click attribution, IP address, and user agent. ATT updates merge into the SDK's existing device context. They do not erase the install ID or attribution identifiers already captured for the install. ## Explicit Layers consent [#explicit-layers-consent] With the 3.3.0 defaults, `setConsent` is the independent control for an app's consent decision. Layers changes consent only when the app calls that API explicitly. The deprecated Swift compatibility switch described above is the only opt-in exception. * An explicit advertising denial removes IDFA and ATT status from SDK events, adds the applicable ad-user-data and personalization denial signals, and is enforced per destination by server-side conversion forwarding. * In Swift, `consentRequired: true` keeps its existing opt-in behavior: delivery waits for the app's explicit grant. * An app that does not call `setConsent` uses the SDK's normal delivery path; ATT still determines whether IDFA can be included. ## Data the SDK can send [#data-the-sdk-can-send] By default, events sent to `in.layers.com` can include persistent per-install identifiers, the IDFV, the ATT status, the IDFA when authorized, an app user ID after `identify`, event names and properties, app/device context, and captured attribution parameters. Purchase events can include values such as revenue, currency, product ID, and transaction ID. Crash and performance behavior differs by wrapper: | Wrapper | Default behavior | | ------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------- | | Native Swift | Does not attach its exception or MetricKit modules, so it does not collect crash or performance data by default | | React Native / Expo | Does not auto-collect crash or performance data | | Flutter | Exception capture is enabled by default and can be disabled with `automaticExceptionTrackingEnabled: false` | | Unity | Exception and performance capture are enabled by default and can be disabled with `AutoTrackExceptions = false` and `AutoTrackPerformance = false` | ## The privacy manifest Layers ships [#the-privacy-manifest-layers-ships] Starting in SDK 3.3.0, each native package's `PrivacyInfo.xcprivacy` contains only the required-reason APIs used by that package: | Package | Required-reason declarations | | ----------------------------------------------------------------- | --------------------------------------------------------------------------- | | Swift, Flutter, Unity | User Defaults `CA92.1`, file timestamps `C617.1`, system boot time `35F9.1` | | React Native (including Expo through its React Native dependency) | File timestamps `C617.1` | The SDK manifests do not set `NSPrivacyTracking`, `NSPrivacyTrackingDomains`, or `NSPrivacyCollectedDataTypes`. They describe the SDK package's required-reason API use; they are not a substitute for the host app's App Store Connect submission or an app-level privacy manifest. ## Info.plist keys [#infoplist-keys] * **`NSUserTrackingUsageDescription`** — required before your app requests ATT permission. The Expo plugin and Unity post-build processor can write it from configuration; native Swift, React Native, and Flutter apps add it in their app target. * **`SKAdNetworkItems`** — add the identifiers required by the ad networks your app uses. Expo and Unity can write their configured lists. * **`NSAdvertisingAttributionReportEndpoint`** — configure this only when Layers should receive the app's SKAdNetwork postbacks. iOS supports one endpoint per app. ## Attribution controls [#attribution-controls] * Clipboard attribution is off by default and is enabled per app. When used, iOS displays its paste notification. * The SDK never includes IDFA unless ATT is authorized. ## See also [#see-also] * [Attribution](/docs/sdk/attribution) — how ATT, clipboard attribution, and Install Referrer feed attribution. * [Installation](/docs/sdk/installation) — per-platform setup, including ATT and SKAdNetwork configuration. * [Data protection](/docs/api/operational/data-protection) — retention and identifier handling at ingest. * [Security & compliance](/docs/api/operational/security-and-compliance) — sub-processors, encryption, and data-subject requests.