IDFV is a type of universally unique identifier (UIUD) that is assigned to a specific iOS app developer account and can be used across multiple apps under the same developer. The IDFV value is identical for apps that are published under the same developer and are running on one device. If there are multiple apps on one user device run by different developers, each of them are assigned different IDFV values. Apps on different devices also hold different IDFVs regardless of the developer.
An IDFV consists of 32 randomized characters and four dashes in between. App developers that incorporate IDFV into their apps can assign a unique IDFV string when a user install’s their app. The IDFV enables first-party data collection, which are data collected directly from users who interact with the app owned by the developer. If a user has multiple apps from one developer installed on their device, the developer will be able to track user data across all the apps they own. IDFVs are removed once a user uninstalls all apps run by that developer.
Identifier for advertisers (IDFA) and IDFV are both used by Apple to track user engagement with iOS apps. The two identifiers, however, are designed for different purposes and have different privacy regulations.
IDFAs are device-specific, meaning that each user device is assigned one unique identifier that does not change across apps or platforms. However, IDFVs are developer-specific and only hold the same values across apps installed on a device owned by the same developer. As such, they have different standards in assigning identifiers with limitations in IDFVs depending on the context.
IDFA and IDFV serve distinct purposes in mobile marketing. IDFA is primarily used for tracking attributions by gathering user-level data such as app installs and ad engagement. This data also enables marketing activities and ad personalizations. On the other hand, IDFV is employed by app developers to monitor user behavior within their own apps, and are unable to track attribution data. Developers often use IDFV for cross-promotions among their specific app portfolios.
Previously, iOS users were opted in by default to share their IDFA with marketers unless they chose to opt out. This operation system raised privacy concerns, which is why Apple introduced the App Tracking Transparency (ATT) framework. Users are now opted out by default and apps have to ask for permission to track upon installation, hence giving users more control of privacy management. IDFVs are considered a more privacy-friendly identifier that does not violate user privacy. There are more boundaries to tracking with IDFVs as it is limited to the app ecosystem of a single developer.
Using IDFV helps developers gather data about how users interact with their specific apps, like which features they use most or how frequently they use each app. They are able to perform cross-examinations between apps and compare the performance of each. In turn, developers can come up with strategies for cross-promotion and relay marketing activities between apps.
IDFV tracking is also useful in frequency capping for ads. By monitoring how many times a user sees a specific ad, developers can make sure that the same ad does not get displayed on the other app and there is no overlapping content across apps.