Firewall: block app data

A no-root firewall that lets you decide which apps may go online — cut mobile data, silence background traffic, block adult or gambling sites on a child's phone, or switch roaming off while travelling. Allow or block every app separately on Wi-Fi, mobile data and roaming, block whole lists of tracking, malware and phishing domains, and see in the log which app reached which destination. Silencing background traffic also cuts your data usage. Everything runs on your device — your traffic never leaves it.

■ Per-app, per-network rules

• Tap the Wi-Fi, mobile-data or roaming icon next to an app to allow or block it on that network.

• A blocked app is refused at once and shows its own offline state.

• Every app with the internet permission is listed; search or filter by user, system, blocked or changed.

• Allow or block every app shown in one go.

• Each app's details: data usage, list whitelist, its own destination rules, per-app logging and a daily MB limit.

■ Eight filter lists

Switch one on and its domains are blocked.

• Trackers & analytics — analytics and behavioural-tracking domains. This list alone acts only in browsers, in keeping with Google Play policy.

• Malware & phishing — from public threat feeds.

• Threat intelligence — scam sites, botnet servers.

• Torrent trackers — BitTorrent hosts.

• Adult content — a large list.

• Social networks — Facebook, Instagram, TikTok.

• Gambling — betting and casino domains.

• Fake news.

Enabled lists update once a day on Wi-Fi, or on one tap.

■ Your own rules

• Custom rules — domains you always block or always allow. An allow rule beats every list.

• Per-app destination rules — long-press a log row to block or allow one domain for that app only.

■ The connection log

• Which app reached which domain or IP, allowed or blocked, and why.

• Search by host or app, or show blocked entries only.

• Export as CSV. Entries expire after 30 days.

• Optional alerts when a new connection opens.

■ Watch and cut your data usage

• Bytes sent and received per app, by day, week or month.

• Daily and monthly alerts for your total usage.

• Lockdown — block everything except the apps you marked "allow in lockdown".

• Block while the screen is off, and block newly installed apps until you allow them.

■ Encrypted DNS

DoH and DoT hide which sites you visit from your network and your ISP. Choose the provider; it falls back to plain DNS if the secure connection fails.

■ Everyday convenience

• Quick Settings tile and home-screen widget.

• Turns itself back on after a reboot, and resumes if Android stops it.

• Allow local network access (printers, casting), or disable IPv6.

• Back up and restore settings in one file.

• Light and dark themes. 35 languages.

■ About this "VPN"

Android needs the VPN permission to judge each app's traffic, and shows a key icon. This is nothing like an ordinary VPN service.

• Your traffic passes through the app, but only inside your device — never relayed to our servers or anyone else's.

• Your IP address and destinations do not change. No country switching, no anonymisation.

• Encrypted traffic is never decrypted or stored.

• The only record is the log — which app, when, where. It never leaves the device.

• No account is needed. Crash reports are optional.

• If the key icon is gone, the firewall stopped; open the app and it resumes.

■ Good to know

• Android allows only one active VPN, so it cannot run alongside another VPN app.

• If Android's Private DNS names a specific provider, lookups are encrypted end to end, so the filter lists see no domain and match nothing. Per-app rules are unaffected — “Automatic” is usually fine; use “Off” if names stop appearing.

■ Free trial and one-time purchase

• Everything is free for 3 days after you install it — no feature limits, no ads.

• To keep using it afterwards, buy "Unlock full version" once inside the app. It is a one-time purchase: no monthly or yearly fee.

• Restore it with the same Google account when you change phone.