About identification

Identification connects the anonymous device the SDK runs on to a real person in your app. Once you identify a user, you can target them with audiences and analyze their interviews alongside everyone else’s. This page explains the model; each platform page shows the exact calls.

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External ID

An external ID is your own stable identifier for a user, typically the ID from your auth system. Set it after login or whenever you know who the current user is. The SDK persists the external ID locally and reuses it across sessions until you reset. Use the external ID to match a participant in Pillow back to the same user in your own systems.

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User properties

User properties are durable traits you attach to a user for targeting and analysis: a plan tier, a verified flag, a lifetime value. Properties persist locally and travel with the user across sessions. Properties support three value types:

• string
• boolean
• number

You can clear a single property or all of them; clearing updates local state, and you can set new values whenever you want to target the user differently.

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When to identify

• After login, or as soon as you know the user’s identity.
• When a trait changes that you target or segment on (for example, a plan upgrade).

Identification is safe to call before the network is ready. The SDK queues it and applies it when the connection returns (see Sessions).

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How it relates to reset

Identity and properties live on the device until you call reset() on logout. Reset clears the external ID and properties and starts a fresh anonymous session, so the next user doesn’t inherit the previous one. See Sessions.

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Per-platform reference