Identifier for vendor (IDFV)
What is Identifier for vendor (IDFV)?
Identifier for Vendor (IDFV) is a universally unique identifier assigned by Apple to iOS apps from the same developer account. IDFV enables app developers to track user behavior across their own app portfolio on a single device while maintaining user privacy. Unlike device-wide identifiers, IDFV values remain consistent only for apps published under the same Apple Developer account on one device.
How it works
IDFV operates through Apple's iOS identifier system with specific assignment rules. The identifier consists of 32 randomized alphanumeric characters separated by four dashes, creating a format like 'XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX'. When a user installs an app, iOS automatically assigns an IDFV that remains constant for all apps from that developer on the device.
Assignment Logic
Apple assigns identical IDFV values to apps from the same developer account on one device. Different developers receive different IDFV values, even on the same device. The same developer receives different IDFV values across different devices, ensuring device-level privacy protection.
Persistence and Reset
IDFV persists until a user uninstalls all apps from that specific developer. When the last app from a developer is removed, iOS generates a new IDFV if the user later reinstalls any app from that developer. This reset mechanism provides users with natural privacy protection through app management.
Why it matters
IDFV provides privacy-compliant user tracking that helps developers optimize their app ecosystems without violating Apple's privacy frameworks. Unlike IDFA, which requires explicit user consent through App Tracking Transparency prompts, IDFV operates automatically within developer-owned app portfolios. This makes IDFV crucial for first-party data strategies, especially as iOS 14.5+ limited IDFA availability to approximately 25% of users globally. Developers use IDFV for cross-promotion campaigns, user journey analysis, and lifetime value measurement across their app portfolio, enabling more effective monetization strategies within privacy boundaries.
How to Implement IDFV Tracking
Start by integrating IDFV collection into your iOS app development workflow. Access IDFV through the UIDevice class in iOS using the 'identifierForVendor' property, which returns the current IDFV string for your developer account. Implement IDFV tracking in your analytics system to connect user sessions across your app portfolio.
Establish data collection standards for IDFV usage across all apps in your portfolio. Create unified user profiles that link IDFV data with in-app events, purchase behavior, and engagement metrics. Ensure your privacy policy clearly explains first-party data collection practices.
Combine IDFV data with other first-party signals like user accounts, email addresses, or phone numbers for more comprehensive user identification. Mobile measurement partners like Airbridge can help integrate IDFV tracking with broader attribution and analytics strategies, providing unified reporting across your entire app ecosystem while maintaining compliance with Apple's privacy requirements.
Related concepts
| Term | Relationship | Description |
|---|---|---|
| IDFA | Contrast | Device-wide identifier requiring user consent, while IDFV operates within developer boundaries |
| App Tracking Transparency | See also | Apple framework that doesn't affect IDFV usage but impacts cross-app tracking |
| Device ID | Parent | Broader category of identifiers that includes IDFV as a vendor-specific variant |
| Mobile Attribution | Solution | Attribution systems that can leverage IDFV for first-party measurement |
| First-Party Data | Method | IDFV enables collection of first-party data within developer app ecosystems |
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