Privacy Policy

What happens on your device

When protection is on, iOS installs a system content filter that AdStop supplies verdicts for. As you browse, iOS asks the filter about the addresses your apps and Safari are trying to reach. That evaluation happens on your device.

AdStop uses a compact on-device blocklist prefilter to answer most requests instantly and offline. The prefilter is the same for every user and contains no information about you.

Only a small fraction of requests that look like possible blocklist matches trigger a network lookup.

Private lookups

When the prefilter needs confirmation, your device performs a private information retrieval query against the AdStop blocklist service. PIR lets your device learn whether an item is in a server's set without the server learning which item was requested.

The query is encrypted. Our service computes over it blindly and returns an encrypted answer that only your device can read.

These lookups are also sent through Apple's Oblivious HTTP relay before they reach our gateway. The relay strips the originating IP address, so our lookup servers receive anonymous encrypted requests.

What we do not do

• No user accounts, sign-ups, or logins.
• No third-party analytics or advertising SDKs in the app.
• No selling, renting, or sharing of your data.
• No profile of your browsing, interests, or behavior.
• No collection of your name, email, contacts, location, or device identifiers for tracking.

Payments

App Store purchases are processed by Apple. Apple handles payment and Family Sharing. We receive Apple's cryptographically signed confirmation that the app is allowed to use the service; we do not receive your payment card, billing address, or Apple ID email.

Apple's handling of purchase data is governed by Apple's Privacy Policy.

The website

getadstop.com is a static site with no analytics scripts and no advertising or tracking cookies. Like any web server, our host may keep short-lived operational request logs, such as IP address and requested page, to run and secure the site.

Those logs are not used to profile visitors and are not combined with any in-app data.

Children and Family Sharing

AdStop is a general-audience utility and is not directed at children. Because it does not collect personal information, it does not knowingly collect information from children. If you enable Family Sharing, the same privacy properties apply to every device in the family group.

Changes to this policy

If this policy changes, we will update this page and the last updated date. Material changes will be highlighted here before they take effect.

Technical notes

On-device prefilter

A downloaded Bloom filter lets your device answer most checks locally. A miss is a definitive local allow with no network call. A hit is only maybe and must be confirmed privately.

Private lookup path

A prefilter hit triggers an encrypted /queries request with an anonymous access token and configuration identifier. Our service computes over the encrypted query and returns an encrypted response that only your device can decrypt.

Unlinkability

Access tokens use Privacy Pass blind signatures, so a token used at lookup time cannot be tied back to when or how it was issued.

Fail-open behavior

If a lookup cannot complete, AdStop allows the request rather than blocking it. Blocking of known malicious & phishing sites is a best-effort layer on top of ad and tracker blocking, not a guarantee.

Contact

Questions about privacy? Email support@getadstop.com.