An install referrer is a unique, anonymous string of characters specific to Android devices used for measuring install ad performance.
What is an install referrer?
An install referrer is several fields of content that contain information about a specific install. It is unique to Android devices and enables marketers to attribute ad activity via the relevant Android app store. This is a deterministic attribution method.
In most cases, the term “install referrer” refers to the Google Play Install Referrer API, however, other Android app stores (such as Xiaomi, Samsung and Huawei) offer install referrer attribution as well.
How does it work?
When a user clicks on a mobile ad to download an app, certain parameters are appended to the link. These parameters are sent to the Google Play Store (or other app store, depending on device settings) when the click occurs. After the install, when the user launches the app for the first time, the string of parameters is sent to the attribution provider via API.
App stores that offer install referrer
Google Play has offered an install referrer attribution method for several years. This install referrer provides Android marketers with an additional attribution method in cases where Google Play is the default app store on the device (the majority of Android devices).
Some newer Huawei mobile devices do not have Google Play Service by default, only Huawei’s proprietary app store, Huawei AppGallery. Huawei also offers an install referrer for retrieving ad activity. This has been supported by AppsFlyer since July 2020.
Samsung Galaxy Store
Samsung Galaxy Store, which comes preinstalled on Samsung mobile devices, also reports ad activity data over an install referrer API. This capability has been supported by AppsFlyer since December of 2020.
Xiaomi GetApps is the official app store for Xiaomi devices. GetApps has install referrer capabilities for measuring installs that occurred via the store on Xiaomi devices.
Why are install referrers important to attribution?
Accuracy. Install referrers are one of the most accurate methods of measuring user engagement with ads. The install referrer method is deterministic and guarantees as close to 100% accuracy as is possible in mobile attribution.
Together with ID matching, Android marketers benefit from two highly accurate deterministic attribution methods, where install referrer is a reliable fallback in the absence of GAIDs or OAIDs.
Reliability. In the install referrer process a custom attribution ID (which cannot be reset) is automatically added to the referrer string by the attribution provider before being sent to the app store. In turn, it removes the need for a network configuration, leaving the attribution provider dependent only on itself to carry out attribution successfully.
Privacy. The install referrer does not rely on any persistent identifier from the device (GAID or OAID) in order to carry out attribution. It is a privacy-centric method for attribution that doesn’t rely on user-level data while still being highly accurate.
Fraud protection. The Google Referrer API significantly reduces the amount of install hijacking fraud that had previously posed a risk with the integrity of the install referrer. This is achieved by authenticating referrer data and actively blocking referrer injection. In other words, the newer install referrer allows marketers to understand what users are doing between a click and install. In turn, marketers are better prepared to combat install hijacking fraud, as well as to make better product and marketing decisions.
Global growth. Install referrer attribution for multiple app stores means that marketers can successfully measure campaigns across multiple Android operating systems, without compromising on accuracy. Marketers aiming to grow into regions where Xiaomi, Samsung and Huawei devices are popular can make smart business choices without having to worry about measurement.