5 Essential Codes For Digital Ad Tracking


Rachel Hill • June 11, 2020

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In the fall of 2007, Apple released the iPhone 1 and kickstarted a new era of mobile technology. The following year, Google launched the Android 1.0 with an operating system that quickly overtook many third-party competitors. These devices revolutionized the way people consume content and browse the internet. Up until this point, digital advertisers had primarily relied on cookies to track users’ activity through the internet and to show them highly relevant and targeted advertisements. 

However, these professionals soon discovered that although cookies could be used on mobile devices, their reach was limited and not conducive across different apps and browsers. Finding a modification for cookies became increasingly important as mobile devices soared in popularity. 

Which brings me to the purpose of this blog post, the mobile-friendly supplement to traditional cookies: advertising ID’s. These ID’s are a series of unique numbers and letters that are assigned to a device on which a specific operating system (OS) is installed. These mobile advertising ID’s work together with traditional cookies and desktop tracking. Here is everything you need to know about the top 5 codes used for mobile ad tracking. 

Currently, there are two main types of advertising ID’s. They are known as AAID’s and IDFA’s.
 
1. AAID “Android Advertising ID”
This term is also commonly known as GAID or “Google Advertising ID.” This code is exclusive to AndroidOS devices and is comprised of a series of numbers and lowercase letters that are always clear (unhashed).In relation to advertising, the AAID of a device can be tracked and recorded in a bid request (along with the standard included information: platform, time of impression, pixel tags, cookies, and the IP address) that Google Ad Exchange can then use to sell an impression. 

 2. IDFA “Identifier for Advertisers”
This code is exclusive to Apple iOS devices and consists of a series of numbers and uppercase letters that can appear either clear or hashed. 

Both of these codes have the same purpose: to assign a unique value to a device and to enable advertisers to track data such as installation of apps or clicks. By identifying the device where the action takes place, advertising professionals can create a clearer picture of their target demographic. Also, the user can control the amount that their AAID or IDFA tracks their preferences by either periodically resetting it or enabling a setting called "Limit Ad Tracking" (LAT), which prevents advertisers from utilizing the code for behavioral advertising. The only significant difference between AAID’s and IDFA’s lies in the distributor: Google or Apple. 

Before advertising ID’s were launched, there were three fixed codes that advertisers used to track users’ activities and preferences: an IMEI and a MAC address.

3. UDID “Universal/Unique Device ID”
Before the IDFA code was created, advertisers could track actions on iPhone iOS with an UDID code. This was helpful for advertisers because it could not be disabled or modified by the user. However, in 2012 with the release of iOS6, Apple transitioned to using IDFA’s to allow users increased control and privacy over their information. 

4. IMEI “International Mobile Equipment Identity”
This term refers to a 15 or 17 digit code that is assigned to any phone (iPhone or Android) operating on a GSM (Global System for Mobile Communication) network. It can be commonly found on the sim card, in the settings app, or sometimes engraved on the back of a device. An IMEI code is considered a permanent method to identify a device.

5. MAC Address “Media Access Control Address”
This term refers to a code comprised of six sets of two digits or characters, separated by colons. It can be found on a computer’s (smartphone or desktop) network interface control (NIC). Like IMEI codes, it is unable to be reset by the user. 

Both Google AndroidOS and Apple iOS privacy policies prohibit apps from transmitting IMEI, UDID, or MAC address codes with AAID’s and IDFA’s. This is to protect the users’ right to privacy. Unless advertisers have explicit consent, they are unable to track behavior by using both advertising ID’s (AAID’s and IDFA’s) and permanent device identifiers (IMEI, UDID, or MAC address codes). For example, it was major news in 2017 when Uber’s iOS app was discovered collecting a variety of non-resettable device identifiers. Apple CEO Tim Cook threatened to have the app removed permanently if they did not abide by their privacy policies. Google’s Play Store takes the same stance when it comes to protecting the privacy of their users.

So, whether you are a seasoned advertising professional or a business owner venturing into the world of digital ad tracking, these codes are vital to understand. You will undoubtably encounter both IDFA and AAID codes because the market is split between Apple and Google users. And, in order to understand the functionality of modern advertising ID’s, it is important to have a basic knowledge of their predecessors: UDID, IMEI, and MAC address codes. 

5 Essential Codes For Digital Ad Tracking

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