Anti-tracking · iOS, Mac, Android

Stop apps from tracking you — across every app, not just your browser

Casper's Cloak blocks Facebook SDK, Google Analytics, Mixpanel, Segment, AppsFlyer, and ~50,000 other trackers — at the network level, in every app on your iPhone, Mac, and Android. iOS App Tracking Transparency only catches some of them; Casper catches the rest, including the CNAME-cloaked first-party-looking trackers browser extensions can't see.

~50,000
Trackers blocked by default
Every app
Not just browsers
Daily
Blocklist updates
Cloaked
Trackers caught (CNAME)

Beyond iOS ATT — actually stop apps from tracking you

Apple's "Ask App Not to Track" prompt only addresses one of the many ways apps follow you. Here's what Casper catches that the system can't.

In-app analytics & telemetry

Mixpanel, Segment, Amplitude, FullStory, Hotjar, and every other behavioral analytics SDK report back at the network level. They're invisible to ATT, invisible to your browser. Casper blocks the connections directly.

Fingerprinting + cross-app tracking

Apps and SDKs use device fingerprints (screen + fonts + timezone + accelerometer noise) to re-identify you across apps even with ATT enabled. By blocking the SDKs at the network layer, the fingerprints have nowhere to go.

Facebook / Meta SDK

Embedded in ~30% of mobile apps. Reports your in-app activity back to Meta whether or not you have a Facebook account or are logged in. Casper blocks every connection to graph.facebook.com, connect.facebook.net, etc.

Data brokers + ad networks

LiveRamp, Acxiom, Experian Marketing Services, the IAB cohort. They aggregate signals from thousands of apps into a behavior profile that gets sold. Block the SDK that ingests, break the pipeline.

CNAME-cloaked trackers

Modern evasion: bigsite.com creates an alias (trk.bigsite.com → really hotjar.com). Looks first-party to browsers. Casper resolves the alias chain and blocks based on the actual destination.

Functional logins still work

The default blocklist spares functional endpoints — Google/Apple/Microsoft sign-on, payment, banking, 2FA. You stop being tracked WITHOUT losing the apps you use.

How phone tracking actually works

The pipeline from your tap to a data broker's profile of you. Casper breaks it at step 2.

1

You install a free app

The app developer embeds 3–15 third-party SDKs to monetize: Facebook SDK, Google Analytics, Mixpanel, AppsFlyer, Adjust. You see the app; you don't see the SDKs.

2

Each SDK calls home with device + user identifiers

Every time you open the app, scroll a screen, or tap a button, the embedded SDKs phone home: hashed email, IDFA (when allowed), IP, device fingerprint, timestamps, screen names, button labels. Casper intercepts these connections at the DNS layer and refuses to resolve.

3

Data brokers aggregate signals across apps

LiveRamp, Acxiom, Experian Marketing Services merge the signals from thousands of apps into a single profile per device. Cross-referenced with public records, this profile is more detailed than your credit report.

4

The profile gets sold

To advertisers (obvious), insurers (less obvious — health predictions from app behavior), employers (background-check enrichment), and sometimes governments. The market for this data is multi-billion-dollar.

Casper breaks the pipeline at step 2

The DNS query never resolves; the SDK never reaches its server; the brokers never receive the signal. No profile-building. The app works (mostly — see FAQ on edge cases) because functional endpoints stay open.

Tracker-blocking FAQs

What privacy-conscious users ask first.

A tracker is a third-party SDK or pixel that a free app or website embeds to send your behavior back to a data broker, advertiser, or analytics company. Common examples: Facebook SDK (in ~30% of mobile apps, sends your activity back to Meta even if you don't have a Facebook account), Google Analytics, Mixpanel, Segment, AppsFlyer, Adjust, Branch. They run silently and most users have no idea how many are embedded in the apps on their phone.

Make apps stop tracking you.

Free trial. iOS, Mac, and Android. Block ~50,000 trackers by default — including the ones ATT and browser extensions can't see.