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Overview

Customer identification is a critical first step in the Flock referral system. By identifying your users, you enable:
  • Personalized referral experiences
  • Accurate tracking of referral activities
  • Proper attribution of rewards
  • Access to user-specific campaign data
This guide explains how to implement customer identification across different platforms using Flock SDKs.
Always call the identify() method after a user logs in or when your app starts with an authenticated user. This should be done before triggering any checkpoints or showing placements.

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Implementation

Use the identify method to link a user’s identity with Flock: 
Flock.shared.identify(
    externalUserId: "<USER_ID_IN_YOUR_APP>",
    email: "user@example.com",
    name: "Alice Smith",
    customProperties: [
      "tier": .string("Pro"),
      "subscription": .string("annual")
    ]
)

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Parameters

ParameterTypeRequiredDescription
externalUserIdStringYesYour unique identifier for the user in your system
emailStringYesUser’s email address
nameStringYesUser’s full name
customPropertiesObjectNoAdditional user attributes for segmentation

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About externalUserId

The externalUserId is the primary identifier that links your user in your system to their profile in Flock:
  • It should be unique and stable for each user
  • Typically, this is the same ID you use in your database

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Custom Properties

Custom properties allow you to segment users and personalize referral experiences:
  • Use them to track user attributes like subscription tier, user type, or purchase history
  • These properties can be used for targeting specific user segments in campaigns
  • Format varies slightly by platform (see examples above)
Custom properties should be simple key-value pairs. Complex nested objects are not supported.

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Best Practices

  1. Call Early: Identify users as early as possible in your app’s lifecycle
  2. Consistent IDs: Use the same externalUserId across all platforms for the same user
  3. Update on Changes: Re-identify users when their information changes
  4. Privacy First: Only send necessary user information
  5. Error Handling: Implement proper error handling around identification calls

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Next Steps

After successfully identifying your users, you can:
  1. Trigger checkpoints to show referral experiences
  2. Display placements at strategic moments
  3. Trigger rewards for completed referrals
For additional help, contact support@withflock.com.