Legal

Privacy Policy

Cyber Shutter is built to protect attention, not harvest it. Your focus history is end-to-end encrypted, on-device by default, and never sold.

Last updated: July 31, 2026

Summary

Cyber Shutter is an on-device firewall. It does not have a server, does not create accounts, and does not transmit, sell, or share your data with anyone — including Antimolecule. Every rule, log, and preference the app creates stays in local storage on your device, protected at rest by Android's standard app-sandbox storage protections, and is deleted the moment you uninstall the app or clear its data in Settings.

What the app does

Cyber Shutter uses Android's VpnService API purely as the mechanism the OS requires to intercept your device's own outbound packets. It is not a general-purpose VPN: no traffic is tunneled to Antimolecule or to any third party. Each packet is either forwarded directly to the real network via a protected socket, or dropped, based on rules you control.

Information we collect

None, in the sense of data leaving your device. The app does store the following locally, purely to provide its own features:

  • Per-app block rules, so you can block or allow specific apps. Stored on-device; deleted via Settings → Storage → "Clear all data," or by toggling a rule off.
  • Global and per-app blocked hostnames, so you can block specific domains. Stored on-device; deleted via Settings → Storage → "Clear all data."
  • DNS query log, which powers the Hosts and Top-Hosts history views. Stored on-device; deleted via Settings → Storage → "Clear DNS query log."
  • Top-host hit counts, aggregate counts shown per app. Stored on-device; cleared together with the DNS query log.
  • UI preferences — theme, first-launch timestamp, the WHOIS lookup URL template, and a "was running" flag used to resume the firewall after a reboot. Stored on-device; deleted via Settings → Storage → "Clear all data."

None of this is a user account, an email address, a phone number, a device identifier, or anything Antimolecule can see. We have no backend, so there is nothing for us to receive even if we wanted to.

What we never collect

  • No analytics, telemetry, or crash-reporting SDKs.
  • No advertising identifiers, no ads.
  • No account creation, login, email, or phone number collection.
  • No third-party SDKs that phone home in the background.

Network access

The only network traffic Cyber Shutter itself initiates is resolving the DNS queries your other apps make through the firewall. Each query is forwarded to the upstream DNS server your device already uses, evaluated against your rules, and answered (or returned as blocked if disallowed). No query content or result is sent anywhere except that standard DNS resolution step — nothing is sent to Antimolecule.

Features that involve the outside world

Two features leave the closed loop described above. Both are user-initiated and neither shares data with Antimolecule:

  • Host WHOIS lookup. Tapping the lookup icon next to a host opens your external browser at a WHOIS site (default https://www.whois.com/whois/{host}, editable in Settings → About). The domain or IP you tapped is sent to that third-party WHOIS provider, not to Antimolecule, and only when you tap the icon. Whatever site you configure is subject to its own privacy policy, not this one.
  • Invite / share sheet. The "Invite a friend" action hands a plain-text message containing the Play Store link to Android's system share sheet or a messaging app you pick. Cyber Shutter does not read your contacts — the suggested-contact chips come from Android's Sharing Shortcuts / Direct Share APIs, which surface your existing most-used share targets without granting the app raw contact access.

Third-party services

Cyber Shutter uses the Google Play In-App Review API to show the standard Play rating prompt without leaving the app. This is a Google-operated component; Google's handling of any data involved is governed by Google's Privacy Policy, not by Antimolecule. Antimolecule receives no data from this feature — it simply opens Google's own review sheet.

No other third-party service is integrated into the app.

Permissions explained

  • VPN service permission — required by Android to run a per-app firewall. The VPN endpoint is virtual and on-device only; no external VPN provider or server is involved.
  • Internet — lets the on-device engine forward permitted packets to the real network on your behalf. Nothing is sent to Antimolecule.
  • Foreground service (including the "special use" subtype) — keeps the firewall running as a visible foreground service while you use other apps. The special-use subtype is declared as DNS-level traffic monitoring and blocking.
  • Query all packages — per-app firewall rules require the full list of installed apps, so you can choose which ones to block.
  • Receive boot completed — lets the firewall restart automatically after a reboot if it was running before.
  • Post notifications — shows the required foreground-service status notification.
  • Wake lock — prevents the OS from killing the firewall mid-packet-flow.

Data retention and your controls

Because everything is stored locally, you are always in full control. Clear the DNS query log or cache individually, or clear all app data, from Settings → Storage. Uninstalling the app removes every rule, log, and preference immediately — there is no server-side copy to also delete, because none exists.

Children's privacy

Cyber Shutter is not directed at children and does not knowingly collect any personal information from anyone, including children, because it does not collect personal information from anyone at all.

Security

All app data is stored in Android's private app-sandbox storage, protected by the OS from other apps. Because no data ever leaves the device, there is no transmission channel for it to be intercepted on.

International users

The app performs no cross-border data transfer of any kind, since no data is transmitted off the device in the first place. This policy applies identically regardless of where you are located.

Lifetime commitment

This policy will not be weakened silently. If a future version ever changes this — for example, by adding an analytics SDK or transmitting usage data — that change will ship as a major, clearly-disclosed, opt-in feature, and this policy (and its effective date) will be updated accordingly before the change ships.

Changes to this policy

We will post any changes here with an updated effective date. Material changes will also be surfaced in-app the next time you open Cyber Shutter after such an update.

Contact

Questions about this policy: hello@antimolecule.com.