AppsFlyer: How the app tracker exposes your data
AppsFlyer is a data broker powering app tracking. Learn the risks and how to block it.
Drafted by automation from the sources listed at the end of this page, and reviewed before publishing. The sources are the part that matters: check them.
What is AppsFlyer?
AppsFlyer is an Israeli data broker headquartered in San Francisco, California. Founded in 2011, it provides a software development kit (SDK) that is embedded into mobile apps to track user activity. These data are used to attribute app installs and in-app actions to specific advertising campaigns, helping marketers measure return on investment.
Who operates it?
AppsFlyer is a private company with around 1,500 employees across more than 20 offices worldwide, including San Francisco, London, Berlin, and Tokyo. It was founded by Oren Kaniel and Reshef Mann, and is included in the Forbes Cloud 100 list of 2025.
What does it do with your data?
The AppsFlyer SDK collects detailed information about your behavior within apps: which screens you visit, how long you stay, how often you open the app, device information (model, OS, language), and your advertising identifier (IDFA/GAID). These data are then combined with other sources to build a behavioral profile. The goal is to enable advertisers to serve targeted campaigns to users with specific profiles, maximizing ad effectiveness.
The company also offers a “Data Clean Room” that lets advertisers and publishers combine data without directly exposing personal information – at least in theory. In practice, the scale and granularity of data collected is enormous.
Why is it blocked?
AppsFlyer is blocked by ad blockers and privacy tools for several reasons:
- Extensive tracking: The SDK tracks user behavior within apps, often without clear consent.
- Data transfer: There is evidence that AppsFlyer shares data with third parties, such as TikTok, without a proper legal basis. In 2025, NOYB (None of Your Business) filed a lawsuit against the company, accusing it of violating the EU’s GDPR.
- Malware risk: In March 2026, malware was found in AppsFlyer’s SDK that replaced Bitcoin wallet addresses, showing that the SDK can be compromised for malicious activities.
- Limitations of DNS blocking: Note that DNS-based blocking (as used by many blockers) does not remove ads served from the same domain as content, nor does it hide your IP address. Additionally, blocking may break functionality of some apps, as many rely on the SDK to work properly.
How to protect yourself?
- Use ad and tracker blockers with lists that include AppsFlyer domains (like
appsflyer.comand its SDK subdomains). - Prefer privacy-friendly apps or use versions without tracking SDKs.
- On iOS or Android, adjust privacy settings to limit ad tracking.
Tools like hado99 can help block known trackers, but no solution is perfect. Combine techniques and stay informed.
Understanding how companies like AppsFlyer operate is the first step to making conscious choices about which apps to install and what data to share.