Sitr (سِتْر — "covering, protection") blocks adult, gambling and dating sites and enforces SafeSearch on every app on your phone — built for Muslim families, useful for anyone who wants a cleaner internet without being watched.
PRIVATE BY DESIGN, NOT BY PROMISE
Most content filters route your traffic through their servers or phone home about what you visit. Sitr does neither, and you don't have to take our word for it:
• Filtering happens on your device, by DNS. Sitr looks at the hostname your apps ask for, decides in memory, and discards it. Nothing is logged or sent.
• Allowed lookups go to the DNS server your network already uses — never to a Sitr server or any third-party resolver.
• The blocklist is identical for every user and published openly, so we have no way to see which sites you visit — and you can see and contest every rule.
• No account, no analytics, no crash reporting, no ads, no third-party SDKs. Analytics aren't "off by default" — they don't exist in the code.
• Open source with a reproducible build: anyone can rebuild the app and compare it against the published checksum.
WHY ANDROID SHOWS A VPN KEY ICON
Android's only system-wide filtering mechanism is a local VPN. Sitr's VPN is DNS-only: the tunnel routes nothing but DNS lookups, and the app cannot see, proxy, or inspect any other traffic. There is no TLS interception and no Sitr server in the path. The design and its limits are documented in the public threat model.
WHAT IT DOES
• Blocks adult content, gambling, and dating sites (gambling and dating are optional categories you can toggle)
• Forces SafeSearch on Google, Bing, and DuckDuckGo, and YouTube Restricted Mode
• Per-site allow and block lists, stored only on your phone
• Optional guardian PIN so settings can't be loosened casually
• Optional Sitr Family household: shares lists across devices, end-to-end encrypted, unreadable to us
• Shows a red "protection inactive" warning if filtering ever stops — another VPN takes over, Private DNS bypasses it — instead of pretending
• Supports managed configuration for organisations and Family Link
WHAT IT DOESN'T DO
No monitoring. Sitr never records, reports, or shows anyone what you or your children browse. No screenshots, no location, no app lists, no accessibility service. The optional Family plan stores exactly one thing on our server: an end-to-end-encrypted household-settings blob we cannot decrypt — household preferences, never browsing.
Honest limits: a user-set strict Private DNS hostname or a browser's own "Secure DNS" bypasses DNS filtering. Sitr detects the first and warns you.
Source code, blocklist, and appeals: https://github.com/terrancoder/sitr
Adult-content filter + SafeSearch, entirely on-device. No account, no tracking.