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The best free firewall apps for Android are Rethink: DNS + Firewall + VPN for most no-root users, NetGuard for simple per-app blocking, AFWall+ for rooted phones, and ShizuWall for Android 11+ users who want to avoid both root and a local VPN. The 12 options below use different methods, so DNS blockers, traffic monitors, root firewalls, and true per-app firewalls are compared separately rather than treated as identical.
An Android firewall can deny an individual app access to Wi-Fi, cellular data, or selected destinations. The right app depends mainly on whether you can use Android’s single VPN slot, whether your phone is rooted, whether Shizuku is available, and whether you want firewalling, DNS filtering, traffic monitoring, or all three.
Key takeaways
- Rethink is the strongest general-purpose free, open-source, no-root choice when firewall rules, DNS filtering, tracker blocking, and logs are all useful.
- NetGuard is the clearest simple option for separate per-app Wi-Fi and mobile-data blocking, but its local VPN prevents normal simultaneous use of another VPN.
- AFWall+ requires root but uses Android/Linux firewall controls, while ShizuWall targets Android 11+ through Shizuku without root or a local VPN.
- DNS filtering blocks selected domains rather than necessarily cutting off every connection from an app, so a DNS firewall is not identical to a per-app firewall.
- Android normally permits only one active VPN service, making local-VPN firewalls incompatible with many Mullvad, Proton VPN, WireGuard, Tailscale, and work-VPN setups.
- Blocking network access can reduce network-based tracking and background data use, but it cannot erase data already stored on the phone or stop every form of tracking.
What does an Android firewall actually do?
An Android firewall controls network traffic generated by apps, but “firewall” describes several different kinds of tools. A true per-app firewall can deny all network access for an app or separately deny Wi-Fi and mobile data. A DNS filter blocks lookups for selected domains, and a traffic monitor may show connections without blocking them.
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| Control type | What it blocks or shows | Best use | Important limitation |
|---|---|---|---|
| Per-app firewall | Most or all network traffic from a selected app | Stopping an app from connecting at all | The app may stop syncing or become unusable |
| Wi-Fi/mobile-data control | Access over Wi-Fi, cellular data, or both | Saving mobile data while allowing home-network access | Available controls vary by app and Android behavior |
| DNS filtering | Lookups for known ad, tracker, malware, or unwanted domains | Blocking selected destinations while keeping an app online | It does not necessarily block hard-coded IP addresses or every app connection |
| IP or address filtering | Selected IP addresses or network destinations | More targeted blocking than disabling an entire app | Addresses can change, and encrypted or shared infrastructure complicates rules |
| Traffic monitoring | App data usage, connection events, or destinations | Finding background activity and troubleshooting | Monitoring alone does not prevent connections |
| Remote VPN | Encrypts or reroutes traffic through a remote server | Network-path privacy and remote access | A VPN alone is not automatically a per-app firewall |
Which free Android firewall is best?
Rethink is the best overall choice for most users who want a no-root firewall plus DNS filtering and network visibility. NetGuard is better when the priority is a focused, simpler allow-or-deny interface. AFWall+ is the specialist choice for rooted devices, and ShizuWall is the most interesting no-root, no-local-VPN option for technically confident Android 11+ users.
| Need | Best starting point | Why | Main compromise |
|---|---|---|---|
| Firewall plus DNS, tracker blocking, and logs | Rethink | Combines per-app rules, DNS filtering, blocklists, and traffic visibility | More settings make troubleshooting harder |
| Simple no-root app blocking | NetGuard | Separate Wi-Fi and mobile-data controls are easy to understand | Uses Android’s local VPN slot |
| Rooted phone and granular rules | AFWall+ | Uses lower-level Android/Linux firewall controls | Root creates security and compatibility risks |
| No root and no local VPN | ShizuWall | Uses Shizuku and Android native framework controls | Requires technical setup and may need reactivation |
| Visual data charts and alerts | GlassWire | Combines usage monitoring with simple blocking | Less focused on deep privacy rules |
| Ad blocking plus firewall controls | AdGuard for Android | Provides firewall rules inside a broader filtering product | The complete product is not wholly free |
12 best free firewall apps for Android
1. Rethink: DNS + Firewall + VPN — best overall
Rethink is the best overall free firewall app for Android for users who want more than a basic on/off switch. Rethink uses a local VPN firewall and can provide per-app blocking, connection logs, IP blocking, background and locked-device rules, DNS-over-HTTPS or DNS-over-TLS options, tracker and ad blocklists, and optional WireGuard VPN functionality. The official firewall documentation describes per-app, category, background, locked-device, and permanent rules.
- Root: Not required.
- VPN: Uses Android’s VPN APIs for firewall functions; it can also provide an optional remote WireGuard VPN.
- Best for: Users who want firewalling, DNS filtering, tracker blocking, and detailed logs in one app.
- Free status: The Android app is free and open source; hosted DNS and VPN services can have separate free or paid tiers.
- Weakness: The combination of firewall, DNS, blocklists, logs, and VPN options is more complicated than NetGuard.
Rethink can conflict with another VPN because its firewall normally needs the local VPN slot. Its recent documentation includes “Always-on VPN” and “Block connections without VPN” controls, but users should still test exclusions and other VPN apps on their particular Android build. The official Rethink download page currently lists build v055z with an August 2, 2026 release signal; verify the live page before publication because app versions change.
Verdict: Choose Rethink when you want the most capable no-root free option and are willing to learn its rule and DNS model.
2. NetGuard — best simple no-root firewall
NetGuard is the best simple free Android firewall for denying internet access to individual apps without root. NetGuard uses a local VPN and presents separate Wi-Fi and mobile-data controls beside each app. The project also lists IPv4 and IPv6 support, TCP and UDP support, system-app blocking, roaming controls, notifications, and optional network-use logging on its official site.
- Root: Not required.
- VPN: Required for its local filtering and normally occupies Android’s one VPN slot.
- Best for: Users who mainly want to allow or deny internet access per app.
- Free status: Core per-app blocking is free; traffic logs, per-address filtering, export functions, and other advanced tools are Pro or donation-unlocked depending on distribution.
- Compatibility: The Google Play listing states Android 5.1 and later.
NetGuard is less comprehensive than Rethink for DNS filtering, but its narrower interface can be easier to manage. GitHub and F-Droid distribution follows a donation model, while Google Play purchases are tied to the Play version, according to the project’s distribution information.
Verdict: Start with NetGuard if “block this app on Wi-Fi or mobile data” is the main requirement and another VPN is not essential.
Recommended Free Tools
3. AFWall+ — best for rooted phones
AFWall+ is the strongest specialist option for a rooted Android phone because it applies lower-level Android/Linux firewall controls instead of using the normal no-root VPN slot. AFWall+ lets advanced users build rules for applications and network categories, making it suitable for granular Wi-Fi, cellular, VPN, and local-network policies. The AFWall+ project repository identifies root as a prerequisite.
- Root: Required.
- VPN: Does not need the standard local VPN slot for its core firewall operation.
- Best for: Experienced users who already accept the risks of rooting.
- Strength: Traditional firewall-style control over system packages and network classes.
- Weakness: Rooting can complicate security updates, banking apps, device recovery, warranties, and future upgrades.
AFWall+ is not a complete ad blocker. Its own advertising-blocking guidance explains that firewall rules are not designed to provide fine-grained ad blocking.
Verdict: Choose AFWall+ only when the phone is already rooted or the user understands the consequences of rooting for this specific purpose.
4. ShizuWall — best no-root, no-VPN option for Android 11+
ShizuWall is a notable choice for Android 11+ users who want app-level network blocking without root and without occupying the local VPN slot. ShizuWall uses the Shizuku service and Android native framework controls. The official ShizuWall site describes it as an open-source firewall for Android 11 and later.
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- Shizuku: Required.
- VPN: Designed not to require a VPN.
- Best for: Users who must keep a separate VPN active or want to avoid VPN-based filtering.
- Weakness: Setup is more technical, and Shizuku may need to be reactivated after reboot, particularly with wireless debugging.
ShizuWall is not the beginner choice simply because it avoids root. Shizuku activation, wireless debugging, OEM restrictions, and Android updates create their own maintenance burden.
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Verdict: Use ShizuWall when avoiding the VPN slot matters more than having the simplest setup.
5. GlassWire — best for data monitoring plus blocking
GlassWire is the best fit for readers who want data-usage charts, alerts, and basic firewall controls in the same Android app. GlassWire monitors app network usage, alerts users when new apps access the network, and provides blocking through a local VPN that routes traffic through the device rather than automatically sending traffic to a remote server. Its Android help documentation describes the firewall and local-VPN behavior.
- Root: Not required.
- VPN: Uses a local VPN for firewall functions.
- Best for: Visual monitoring, usage alerts, and straightforward blocking.
- Weakness: It is more of a data monitor with firewall controls than a deep rule engine like NetGuard or Rethink.
- Free status: The supplied evidence confirms a free-use path but does not establish the current feature split or pricing; check the live GlassWire product information before describing a specific feature as free.
Verdict: Pick GlassWire when understanding which apps consume data is as important as blocking them.
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AdGuard for Android suits users whose main goal is ad and tracker filtering with per-app firewall rules available under Protection → Firewall. AdGuard exposes global firewall rules and custom per-app rules, as described in its official firewall documentation.
- Root: Usually not required.
- Best for: Ad blocking, tracker filtering, and firewall controls in one broader privacy product.
- Firewall path: Protection → Firewall.
- Weakness: AdGuard is overkill for users who only want a lightweight app blocklist.
- Free status: Do not describe the complete product as free; premium filtering, licensing, or subscription features may apply.
AdGuard may also compete for Android’s VPN slot depending on the active filtering mode. Users should not run it alongside another local-VPN firewall without checking which service is active.
Verdict: Choose AdGuard when ad and tracker blocking matter more than having a small, dedicated firewall.
7. TrackerControl — best for privacy inspection
TrackerControl is a privacy-oriented local-VPN monitor that helps users inspect tracker and network connections and restrict app behavior. TrackerControl is better described as a privacy firewall and inspection tool than as a conventional port-filtering firewall. Its availability is listed through the F-Droid firewall category.
- Root: Not required.
- VPN: Uses a local VPN model.
- Best for: Identifying tracking connections and understanding what apps contact.
- Weakness: Exact Android compatibility, current release activity, and the availability of every control in the free build should be checked on the current app page.
Verdict: Use TrackerControl when inspection and privacy research are more important than a minimal allow-or-deny interface.
8. personalDNSfilter — best for DNS-based blocking
personalDNSfilter is best for blocking known ad, tracker, malware, or unwanted domains across apps rather than disabling every connection from an app. The app uses local-VPN DNS filtering and host or blocklists. Its listing appears in the F-Droid firewall category.
- Root: Not required.
- VPN: Uses a local VPN for DNS filtering.
- Best for: Selective domain blocking while allowing the rest of an app’s traffic.
- Weakness: DNS filtering generally cannot enforce the same per-app Wi-Fi/mobile-data policy as NetGuard or AFWall+ and may not stop hard-coded IP connections.
Verdict: Choose personalDNSfilter when domain-level filtering is the goal and full app shutdown would be too aggressive.
9. DNS66 — best lightweight DNS/hosts option for older setups
DNS66 is a lightweight DNS and hosts-filtering option, not a modern full per-app firewall by default. DNS66 typically uses a local VPN without root to apply host-based ad and tracker blocking. Its current maintenance, Android-version support, and distribution status need verification before installation; the supplied candidate source is the F-Droid firewall category.
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- Method: DNS and hosts filtering through a local VPN.
- Best for: Straightforward hosts-based blocking on a compatible older setup.
- Weakness: Do not assume current support or describe DNS66 as equivalent to a maintained, full per-app firewall without testing the current build.
Verdict: Treat DNS66 as a legacy or lightweight candidate and verify the build before relying on it.
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10. InviZible Pro — best privacy suite with firewall-related controls
InviZible Pro is a privacy suite for experienced users who want firewall-related controls alongside Tor, DNSCrypt, and I2P features. The combination of routing and privacy systems makes InviZible Pro substantially broader than a simple app firewall. Its availability is listed through the F-Droid firewall category.
- Root: Usually optional depending on the feature.
- Best for: Advanced privacy configurations involving more than app blocking.
- Strength: Combines several privacy and routing technologies.
- Weakness: Beginners may find it difficult to determine which component is blocking or routing traffic.
Verdict: Select InviZible Pro as a privacy suite, not as a direct beginner replacement for NetGuard.
11. Karma Firewall — best minimalist F-Droid candidate
Karma Firewall is a minimalist app-level network-blocking candidate for readers seeking a small privacy-oriented tool. The current implementation, root or VPN requirement, Android compatibility, maintenance activity, and exact rule capabilities should be confirmed from the current listing before installation. The supplied availability source is the F-Droid firewall category.
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- Best for: Users looking for a small firewall rather than an all-in-one suite.
- Current-status caveat: Documentation and established coverage are thinner than for Rethink, NetGuard, or AFWall+.
- Installation advice: Use a current official distribution and avoid unverified APK mirrors.
Verdict: Consider Karma Firewall only after confirming that its current build supports the Android version and control model you need.
12. NetWall — best Shizuku-based alternative candidate
NetWall is a Shizuku-assisted firewall candidate for users seeking no-root app blocking without the standard VPN slot. The supplied sources identify a Google Play listing and the F-Droid firewall category, but current maintenance, exact rule capabilities, and distribution should be verified before making strong claims.
- Root: No root is expected, but Shizuku is generally required.
- Best for: Technically confident users exploring a no-root, no-local-VPN approach.
- Weakness: Current support and feature depth are less established than ShizuWall’s.
Verdict: Treat NetWall as an alternative candidate rather than an equal recommendation to the four leading choices.
Which firewall should you choose?
Choose the firewall according to your phone’s setup and the type of control you need. A no-root user who does not run another VPN should begin with Rethink or NetGuard. A rooted user should consider AFWall+. A user with Android 11 or later who needs another VPN should investigate ShizuWall. A user primarily interested in domains, ads, or trackers may prefer Rethink, AdGuard, or personalDNSfilter.
| Situation | Recommended option | Reason | Do not overlook |
|---|---|---|---|
| I do not want root | Rethink or NetGuard | Both provide no-root per-app blocking | Both normally use the local VPN slot |
| I already use Mullvad, Proton VPN, WireGuard, Tailscale, or a work VPN | AFWall+ if rooted; ShizuWall if compatible | Root or Shizuku approaches avoid the normal local-VPN conflict | ShizuWall needs Shizuku and AFWall+ needs root |
| I mainly want tracker or ad blocking | Rethink, AdGuard, or personalDNSfilter | DNS and blocklists can target domains without disabling an entire app | Known-domain filtering is not perfect |
| I want visual data charts | GlassWire | Monitoring and alerts are central features | Feature limits and pricing should be checked live |
| I want the most granular controls | AFWall+ | Root enables lower-level rule management | Root can break banking, updates, and device recovery workflows |
| I want the least setup | NetGuard | Its core purpose is straightforward per-app blocking | It still requires accepting Android’s VPN prompt |
Does an Android firewall require root?
No, most Android firewall apps do not require root. NetGuard, Rethink, GlassWire, TrackerControl, personalDNSfilter, and similar tools use Android’s VpnService API to route traffic through the phone for local filtering. AFWall+ requires root and can use lower-level firewall controls. ShizuWall uses Shizuku and Android’s native framework controls as a middle path.
Google Play recognizes firewall and device-security apps as an eligible use of VpnService, subject to disclosure, consent, encryption, and policy requirements. The relevant Google Play VpnService policy explains the platform conditions; the policy does not mean every app using VPN APIs is a remote privacy VPN.
Can a firewall run alongside another VPN?
Usually, a no-root local-VPN firewall cannot run normally at the same time as another app that controls Android’s standard VPN slot. Android normally allows one active VPN service, so starting Mullvad, Proton VPN, WireGuard, Tailscale, a work VPN, AdGuard VPN mode, or another local firewall may disconnect or replace the existing service. NetGuard documents this single-VPN limitation.
Split tunneling does not automatically solve the slot conflict. Root firewalls such as AFWall+ and Shizuku-based tools such as ShizuWall are more suitable when a separate VPN must remain active. Rethink can also provide WireGuard-based VPN functionality, but Rethink should not be assumed to coexist universally with every other VPN app.
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How should you set up a firewall safely?
Install from an official distribution, enable the firewall, block one nonessential app, and test before creating broad rules. A cautious first policy prevents a broken notification system or inaccessible banking app from becoming a difficult recovery problem.
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- Install from Google Play, F-Droid, or the developer’s official site. Avoid unofficial APK mirrors.
- Enable the firewall and accept Android’s VPN prompt if the chosen app uses
VpnService. - Start with an obvious nonessential app such as a calculator, offline file viewer, wallpaper app, or offline game that does not need online features.
- Keep the firewall’s persistent notification visible while testing.
- Use connection or DNS logs to identify required destinations.
- Add rules one app at a time and test login, synchronization, notifications, media playback, casting, Android Auto, and work features.
- Do not begin by blocking packages simply because their names start with
com.androidorcom.google.
Rethink gives examples such as file managers, alarm clocks, and calculators that may not need internet access, but an app’s network needs vary by developer, phone manufacturer, and version. Block visible app identities where possible instead of guessing from package names.
NetGuard setup
- Install NetGuard from the official project or its official Google Play listing.
- Open NetGuard, enable the firewall, and accept the Android VPN connection prompt.
- Tap the Wi-Fi icon, mobile-data icon, or both beside an app to deny access.
- Test the app and restore one connection type at a time if a feature breaks.
- Enable advanced logging or address filtering only when the basic policy is working.
Rethink setup
- Install the current build from an official Rethink distribution.
- Enable the Firewall module.
- Decide separately whether DNS filtering and blocklists are needed.
- Review network and DNS logs before creating complex rules.
- Create per-app, category, background, locked-device, or IP rules as needed.
- Enable “Always-on VPN” and “Block connections without VPN” only if the controls behave reliably on the device.
- Add exclusions for apps that must use another VPN or bypass filtering.
- Retest notifications, banking, streaming, and work-profile applications.
ShizuWall setup
- Install ShizuWall from its official distribution.
- Install and start Shizuku.
- Pair Shizuku through wireless debugging or another supported activation method.
- Grant ShizuWall access through Shizuku.
- Select an app and deny its network access.
- Reactivate Shizuku after reboot if the phone requires it.
- Test the rule again after major Android updates.
AFWall+ setup
- Root the phone using a method appropriate for its manufacturer and Android build.
- Install AFWall+ only from a trusted official source.
- Grant AFWall+ root access.
- Select the apps allowed over Wi-Fi, cellular data, VPN, LAN, or other available categories.
- Apply the rules and verify the result.
- Keep recovery access and a rollback plan before changing system-package rules.
- Avoid blocking system packages until the consequences are understood.
What should beginners block?
Beginners should first block clearly nonessential apps, not Android system components. Offline calculators, file viewers, wallpaper apps, and games that do not need online features are safer starting points than Google Play Services, Android System WebView, account components, carrier services, or manufacturer packages.
Do not casually block Google Play Store or Play Services, Android System WebView, push-notification components, Google or Samsung account synchronization, emergency alerts, Find My Device, carrier provisioning, system updates, banking or authentication apps, device-management apps, Bluetooth, casting, Android Auto, or smart-home services. A system component that appears unnecessary may support several unrelated features.
Does blocking internet access remove tracking?
Blocking an app’s network access can reduce network-based tracking, but it does not remove tracking completely. A firewall cannot erase data already stored locally, stop tracking inside another permitted app, prevent browser fingerprinting, prevent sensor or location collection, stop data shared through Android intents, or prevent future transmission after the user allows the app again.
Use “reduces network-based tracking” rather than “stops tracking.” A firewall also does not replace Android security updates or guarantee that an app is safe.
Can an Android firewall block ads?
An Android firewall can block ads either by disabling an app’s network access or by filtering known ad domains, but neither method guarantees ad removal. Per-app blocking may make an app unusable. DNS, hosts, or IP filtering can preserve other app functions, but ads served from the same domain as the app’s content may not be blockable without breaking that content.
AFWall+’s official advertising guidance specifically distinguishes firewalling from dedicated ad blocking. Rethink, AdGuard, and personalDNSfilter are more appropriate when selective ad or tracker-domain filtering is the main objective.
Why does an Android firewall stop working?
Android battery optimization and manufacturer task-killing are common reasons a firewall stops filtering after the screen turns off or the phone reboots. Samsung, Xiaomi, OnePlus, Oppo, Vivo, Huawei, and other manufacturers can suspend background services differently.
- Set the firewall app to unrestricted battery use.
- Allow background activity.
- Disable automatic battery optimization for the firewall.
- Keep the persistent notification enabled when the app relies on it.
- Recheck these settings after major Android or manufacturer updates.
Menu names vary by Android version and manufacturer, so the exact battery path cannot be treated as universal.
Firewall troubleshooting checklist
Another VPN will not connect
Stop or disable the local-VPN firewall, or switch to AFWall+ on a rooted phone or a compatible Shizuku-based firewall. Android normally gives one app control of the VPN interface.
Notifications stop arriving
Temporarily allow the affected app and its required system services, then inspect firewall and DNS logs. Do not assume that blocking only the visible app is harmless because push delivery can involve system components.
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Restore Wi-Fi or mobile-data access for the app, test again, and then use logs to identify whether a required domain or background rule was blocked.
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A banking or streaming app refuses to run
Some apps react to local VPN behavior, root, accessibility services, certificate interception, or unusual routing. Firewalling is not certificate interception, but a local VPN can still trigger an app’s compatibility check. Temporarily disable the firewall to isolate the cause.
DNS filtering breaks websites
Disable the active blocklist or DNS module temporarily, then allow the required domain. Avoid stacking Android Private DNS, Rethink DNS filtering, DNS66, AdGuard, and another VPN without testing because multiple DNS controllers are not automatically additive.
System apps are difficult to identify
Use the visible app identity and logs rather than guessing from package names. Test one rule at a time and keep a record of the last change so the previous state can be restored.
A work profile or managed phone rejects the firewall
Enterprise policy, parental controls, or device-management software may restrict VPN, root, accessibility, Shizuku, or app-level network controls. Check employer or school policy before changing a managed device.
What are the free and paid limits?
“Free firewall” does not mean every feature in every app is free. NetGuard’s core per-app blocking is free, while detailed logs, address filtering, exports, and some advanced tools are paid or donation-unlocked depending on distribution. Rethink’s Android app is free and open source, but hosted DNS and VPN services can have separate paid tiers. AdGuard has premium licensing, and current GlassWire feature restrictions should be checked on its live product page.
| Product or feature | Commercial point | Best fit | Not a good reason to choose it |
|---|---|---|---|
| Rethink optional RPN | Rethink’s FAQ and download information show plans starting at $1.75 per month; verify current terms and fair-use details | Users wanting an integrated Rethink firewall and WireGuard-based VPN ecosystem | Users who only need free app blocking or already have a VPN |
| NetGuard Pro or donation unlock | GitHub/F-Droid distribution describes a donation-based path, including a one-time donation of at least €0.10 for current and future Pro features; Play purchases are separate | Users wanting focused advanced firewall tools | Users needing a remote VPN or simultaneous use with another VPN |
| AdGuard premium | Premium licensing exists, but the supplied evidence does not establish a current US price | Users wanting ad blocking, tracker filtering, and firewall controls together | Users seeking a lightweight, open-source, entirely free firewall |
| GlassWire Android plans | Current Android pricing and feature restrictions require live verification | Users who value visual data charts and alerts | Users seeking deep IP/domain rules or a fully open-source firewall |
A separate commercial VPN can provide remote encryption and location or network-privacy features, but a VPN alone is not a substitute for per-app firewalling. A separate VPN can also conflict with a local-VPN firewall.
Apps older lists recommend cautiously
NoRoot Firewall and Mobiwol should not be recommended automatically from old comparison articles. The supplied evidence does not establish current maintenance and compatibility for either app as of August 18, 2026. If NoRoot Firewall is included elsewhere, it should be labeled a legacy option, checked against a current first-party distribution page, and never downloaded from an unofficial APK mirror. Mobiwol should be excluded unless a current first-party release is established.
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Final recommendations
Install Rethink for the broadest free no-root feature set, NetGuard for the simplest per-app firewall, AFWall+ for a rooted phone, and ShizuWall when Android 11+ users need to avoid both root and a local VPN. Use GlassWire for monitoring, AdGuard for a bundled ad-blocking suite, and personalDNSfilter for selective DNS-domain blocking. Treat DNS66, InviZible Pro, TrackerControl, Karma Firewall, and NetWall as specialized or conditional choices rather than interchangeable winners.
Whichever app you choose, begin with narrow rules, keep recovery access, monitor notifications and synchronization, and remember that Android firewall behavior varies by device manufacturer, Android version, VPN configuration, and managed-device policy.
Frequently Asked Questions
Can a free Android firewall work without root?
Yes. NetGuard, Rethink, GlassWire, and similar apps use Android’s local VpnService and do not require root. ShizuWall uses Shizuku instead and is designed for Android 11+ without root or a local VPN.
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Can NetGuard or Rethink run with Mullvad or Proton VPN?
Usually not in the normal no-root configuration because Android generally allows only one active VPN service. A rooted AFWall+ setup or a compatible Shizuku firewall is more suitable when another VPN must remain active.
Does an Android firewall block all tracking and ads?
No. Per-app blocking can stop network transmission, and DNS filtering can block known ad or tracker domains, but neither method removes locally stored data, prevents every tracking technique, or guarantees that all ads will disappear.
What is the safest Android firewall for a beginner?
NetGuard is the simplest starting point for basic no-root per-app Wi-Fi and mobile-data controls. Rethink is more capable but has more DNS, blocklist, VPN, and logging settings to understand.
The Bottom Line
Bottom line: Rethink is the best overall free Android firewall for most no-root users, NetGuard is the best simple choice, AFWall+ is the best rooted-phone option, and ShizuWall is the best no-root/no-local-VPN candidate for Android 11+ users. Choose based on the filtering method and VPN requirements, not simply on the number of features or the word “free.”
Quick Recap
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