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Router VPN

The VPN to your own router – explained

Why Router VPN uses a VPN, where the tunnel goes, which traffic uses it and why none of your data reaches us. With step-by-step FRITZ!Box setup and troubleshooting. Last updated: October 2026, Router VPN 1.1.1.

Router VPNfree · ad-free
Download Router VPN (APK)

Version 1.1.1 · Android 8.0 or later · 16.7 MB

Checksum (SHA-256): 8b2a3c9944ae8691db20981597deb9586f5c8ff716b119fb1a7264bd30bc8be2

No store needed: when you open it, Android asks once whether installs from this source (for example your browser) are allowed – allow it once. Updates are not automatic; new versions are available here. The app is available in English and German. Router VPN privacy policy.

In short

  • Router VPN connects your phone only to your own router at home, for example a FRITZ!Box. We run no VPN servers; your traffic never passes through us.
  • The VPN is needed so that Softstringsphone and Softstringsphone Pro work away from home through your FRITZ!Box: with your landline number, call list, phone book and incoming calls.
  • You decide what goes through the tunnel. By default only our apps and only connections to your home network – the rest of your internet is untouched.
  • The tunnel is encrypted with WireGuard. Your FRITZ!Box creates the credentials itself; you import them into the app by QR code, file or text.
  • No data collection, no logs, no account, no ads, no tracking, no sharing.
  • The VPN only starts after the app has explained what it does and you have accepted Android's consent dialog. It can be turned off at any time.

Contents

  1. What the VPN is for
  2. How it works
  3. Which traffic goes through the tunnel
  4. Privacy and permissions
  5. Requirements
  6. Step-by-step setup
  7. Common problems
  8. Alternatives
  9. Demo video (text version)

1. What the VPN is for

Softstringsphone and Softstringsphone Pro register with your FRITZ!Box as a telephone. On your home Wi-Fi this works directly. On mobile data or someone else's Wi-Fi, your FRITZ!Box is deliberately not reachable from the internet. Without a VPN you cannot call with your landline number, incoming calls do not reach the phone, and the router's call list and phone book are missing.

Router VPN builds an encrypted tunnel from the phone to your FRITZ!Box. The router then treats the phone as if it were on the home network. The router does not need to open any telephony ports to the internet – which is safer than exposing telephony directly. The same applies to everything else on your home network, such as network storage, the smart home or the FRITZ!Box user interface.

Why a separate app?

Google Play only allows Android's VPN interface (VpnService) in apps whose main purpose is a VPN. That is why, since Softstringsphone 1.1.0 and Pro 2.3.0, the tunnel lives in the standalone, free app Router VPN instead of the phone apps. Both phone apps are among the apps Router VPN sends through the tunnel by default; they automatically call through it and show whether it is running.

2. How it works

Your phone with Router VPN, encrypted WireGuard tunnel over mobile data or other Wi-Fi, your FRITZ!Box at home, behind it the phone network and the home network. There is no developer server. Your phone Router VPN + Softstringsphone WireGuard tunnel, encrypted over mobile data or other Wi-Fi Your FRITZ!Box The tunnel ends here Phone network Home network Developer server does not exist Your phone with Router VPN, encrypted WireGuard tunnel, your FRITZ!Box, behind it the phone network and the home network. There is no developer server. Your phone Router VPN + Softstringsphone WireGuard tunnel encrypted, over mobile data or other Wi-Fi Your FRITZ!Box The tunnel ends here Phone network Home network Developer server does not exist
  1. You create a WireGuard access for the phone in your FRITZ!Box. The router generates the keys and shows the settings as a QR code and as the file wg_config.conf.
  2. You import these settings into Router VPN. They are stored encrypted, only on the phone.
  3. When you switch it on, Router VPN uses Android's VPN function to open the tunnel directly to the address in the settings (Endpoint, usually your MyFRITZ! address). It uses the official WireGuard library. Which apps and destinations use the tunnel is set in the app (section 3).
  4. Through the tunnel, Softstringsphone reaches the FRITZ!Box just like at home, registers for incoming calls and calls through the router with your landline number.

The tunnel ends at your router. Its destination is defined only by the settings your router generated. We do not see your traffic, do not redirect it and have no way to see it.

3. Which traffic goes through the tunnel

You decide – in Router VPN, on each connection under "Settings" → "What goes through the VPN?". The connection's card always shows what currently applies ("Through the VPN: …").

Default for new connections: "Only our apps" · "Home network only". Only Softstringsphone, Softstringsphone Pro and Fritten&Fax use the tunnel, and only for connections to devices at home. All other apps and the rest of your internet bypass the VPN as usual and stay fast.

Router VPN: “What goes through the VPN?” with “Only our apps” and “Home network only”
Settings of a connection

Which apps?

  • Only our apps (recommended) – Softstringsphone, Softstringsphone Pro and Fritten&Fax.
  • Selected apps – for example also the browser, to open the FRITZ!Box interface or network storage.
  • All apps except … – the whole phone except exclusions, such as banking or streaming apps that don't like VPNs.
  • All apps – the whole phone.

Where to?

  • Home network only (recommended) – only connections to the router, phone system, network storage and other devices at home go through the tunnel. The internet stays direct.
  • Everything, including the internet – all traffic of the chosen apps goes out via your connection at home. Useful on open, unknown Wi-Fi. Websites then see your home IP address, and your home upload speed limits browsing. With "Local networks direct", printers, TVs and the hotel Wi-Fi login page stay reachable.

Automatic by network

Optionally, Router VPN picks the rule by itself depending on where you are: one rule "On mobile data", one "In other Wi-Fi networks" (suggested: everything through the tunnel) and one "In your Wi-Fi at home" (suggested: "Rest" – nothing goes through the VPN at home, and it switches back on by itself when you leave). The app recognises home by your own router, without location access (see section 4).

Connections from older versions

Up to version 1.0.1, the FRITZ!Box settings (AllowedIPs including 0.0.0.0/0) sent all of the phone's traffic through the tunnel. Connections set up before the update behave exactly as before ("All apps · Everything"). The app points this out once and offers "Use recommendation" or "Keep as before".

Advanced

Under "Show advanced settings": additional address ranges at home (if your home network has more than one range), name resolution (DNS: as set by the router, from the current network, or your own servers), MTU and keepalive. "Reset to recommendation" restores everything. Your router's WireGuard settings themselves stay stored unchanged.

Note: if "Block connections without VPN" is on in Android's VPN settings, Android only allows traffic through the VPN. Router VPN then sends everything from all apps through the tunnel – otherwise other apps would have no internet – and does not rest at home. The app shows this on the connection.

4. Privacy and permissions

  • No data collection: Router VPN has no account, no server of its own, no advertising or analytics libraries, and sends nothing to us or to third parties.
  • No logs: the app does not inspect, modify, log or redirect the traffic in the tunnel.
  • Recognising home (only with "Automatic by network"): the app asks your own router for its fixed device ID – only through the tunnel or in your own Wi-Fi – and stores it only on your phone. No location access, Wi-Fi names are not read, nothing is sent anywhere else.
  • Your key stays on the phone: the imported settings contain a private key. They are encrypted with AES-256-GCM (key in the Android Keystore), stored only on this phone, excluded from Android backups and never logged. "Delete" on the connection or uninstalling the app removes them.
  • Your consent: before the first start, the app explains on the screen "Before the VPN starts" what the VPN does and that you decide what goes through it. Only after "Continue" does Android ask in its own dialog whether Router VPN may set up a VPN connection. No VPN starts without your consent. While it runs, Android shows a key icon in the status bar.
  • Off at any time: with the switch in the app, the quick settings tile "Router VPN" or in Android under Settings → Network & internet → VPN.
  • Permissions: VPN (Android asks once) for the tunnel; Internet for the connection to your router; Network state to tell mobile data from Wi-Fi (automatic by network); List of apps with an icon in the app drawer so you can choose which apps use the VPN – the list stays on the phone; Camera only when you tap "Scan QR code" – recognition runs on the phone, images are neither stored nor sent; Run at startup so that a VPN that was on is switched on again after a restart.

Full details are in the privacy policy, section Router VPN.

5. Requirements

  • An Android phone with Android 8.0 or later.
  • A FRITZ!Box with WireGuard (FRITZ!OS 7.50 or later) – or another WireGuard router or server, such as OpenWrt, GL.iNet, UniFi or Synology.
  • An internet connection through which the router can be reached: with a public IPv4 address or via IPv6 (see DS-Lite).
  • For calls: Softstringsphone or Softstringsphone Pro, set up with your FRITZ!Box.

6. Step-by-step setup

These steps match the setup help in the app. The FRITZ!Box interface is often in German; the German labels are given in brackets. Menu names can differ slightly depending on the FRITZ!OS version.

A. Create the VPN access in the FRITZ!Box

  1. At home, open http://fritz.box in a browser and log in.
  2. Internet → Permit Access (Internet → Freigaben) → tab "VPN (WireGuard)".
  3. "Add VPN connection" („VPN-Verbindung hinzufügen“).
  4. Choose "Simplified setup" / "Connect a single device" („Einzelgerät verbinden“), then "Next".
  5. Enter a name, e.g. Router VPN, then "Finish".
  6. The router asks for an extra confirmation: dial the key sequence shown on a phone connected to the router (e.g. the landline phone), then "OK".
  7. The page "WireGuard settings of your FRITZ!Box" appears with a QR code and a download button. Leave this page open.

Note: do not choose "VPN (IPSec)" or "Connect networks". The router shows the settings only once; if you closed the page, delete the access in the router and create it again. The QR code and file are a key to your home network: do not share or photograph them, and delete the file after importing it.

B. Import the settings into Router VPN

  1. Install Router VPN – from the home page (soon also on Google Play and in the Galaxy Store). In Softstringsphone, "Install VPN app" takes you straight there.
  2. In Router VPN tap "Add connection" and choose one way:
    • FRITZ!Box open on a computer: "Scan QR code" and point the camera at the screen.
    • FRITZ!Box open on this phone: tap the download button there (file wg_config.conf in "Downloads"), then "Choose file" in the app.
    • Or copy the text of the file and use "Paste text".
  3. Optionally enter a name, e.g. "FRITZ!Box at home".

C. Switch on and test

  1. Turn on the switch of the connection. The app shows "Before the VPN starts" once; confirm with "Continue".
  2. Android shows a "Connection request": allow it with "OK".
  3. Test with Wi-Fi switched off. After a few seconds the state shows "Connected" and "Last answer from the router".
  4. Softstringsphone now shows "VPN active" and registers for incoming calls. You can close Router VPN; the VPN stays on until you turn it off.
  5. Optional: under "Settings" on the connection, choose what goes through the VPN and turn on "Automatic by network" (section 3). For the automatic mode, tap "I am at home: remember router now" once in your Wi-Fi at home – or the app remembers the router by itself the next time it connects.
Router VPN: Add connection with Scan QR code, Choose file or Paste text
Add connection
Router VPN: disclosure screen “Before the VPN starts”
Disclosure before the first start
Router VPN: connection to the FRITZ!Box is connected
Connected
Router VPN: setup help inside the app
Setup help in the app

Tips

  • At home on Wi-Fi you don't need the VPN. With "Automatic by network" it rests there by itself.
  • In Android's VPN settings you can set Router VPN to "Always-on VPN". Android then keeps the last used connection on, even after a restart. Leave "Block connections without VPN" off if only part of the traffic should use the VPN.
  • Only one connection can be on at a time. Switching on another one ends the current one.

7. Common problems

"The router is not answering"
  • Test on mobile data, not on your own Wi-Fi.
  • Check that the access still exists in the FRITZ!Box (Internet → Permit Access → VPN (WireGuard)). If you created it again, import the new settings – the old keys no longer work.
  • Some public Wi-Fi networks (hotels, offices, trains) block WireGuard (UDP). Try mobile data.
  • If the router gets a new internet address, e.g. after the provider's daily reconnect, the app notices the missing answers and reconnects by itself.
"The router's address was not found"
  • Is the phone online? The app tries again by itself in a moment.
  • In the FRITZ!Box, check under Internet → MyFRITZ! Account that the router is registered. After a router restart it can take a few minutes until the MyFRITZ! address is correct again.
"These are not WireGuard settings"

Import the QR code or file from Internet → Permit Access → VPN (WireGuard). The MyFRITZ! address alone or an IPSec access is not enough. If the private key or the address (Endpoint) is missing, the app says so explicitly.

"Android did not allow the VPN" / another VPN is active

Android allows only one active VPN. Switch Router VPN on again and tap "OK" when Android asks. If another app (work VPN, ad blocker using a VPN, the "WireGuard" app) is set as "Always-on VPN", turn that off first under Settings → Network & internet → VPN.

Connection with DS-Lite (no public IPv4 address)

Many cable and some fibre connections have no public IPv4 address of their own. The router is then only reachable via IPv6. The VPN works if your mobile network supports IPv6 too – usually the case on German mobile networks, often not on other Wi-Fi networks. Fix: ask your provider for a public IPv4 address.

Same address range as the other network

Many FRITZ!Boxes use 192.168.178.x. If you are on a Wi-Fi network with the same range (for example at a friend's house with a FRITZ!Box), your home network cannot be reached. Fix: use mobile data, or change your router's address range (Home Network → Network → Network Settings → IPv4 Settings) and then create the VPN access again.

Browsing is slow while the VPN is on

All traffic is going through your home connection, and its upload speed is the limit – typical for connections from version 1.0.x. Fix: choose "Home network only" under "What goes through the VPN?", or "Reset to recommendation" (section 3).

http://fritz.box does not open in the browser

With the default "Only our apps", the browser does not use the VPN. Add the browser under "Selected apps" or choose "All apps". If name resolution is set to "From the current network", reach the router by its address (e.g. http://192.168.178.1).

A banking or streaming app does not work with the VPN

Some apps refuse VPN connections. Choose that app as an exclusion under "All apps except …" – or stay with "Only our apps", where it is not affected anyway.

The automatic mode does not recognise my Wi-Fi at home

The app recognises home by your FRITZ!Box's device ID. For this, "Allow access for applications" must be on under Home Network → Network → Network Settings (usually it already is). With routers that don't provide this ID, the rule for other Wi-Fi networks applies at home. If "Block connections without VPN" is on in Android, the VPN never rests at home.

Incoming calls do not arrive while away
  • Is the VPN running? Softstringsphone shows "VPN active".
  • Turn off battery optimization for Softstringsphone (button in the app's settings, or Settings → Apps → Softstringsphone → Battery → Unrestricted). Samsung, Xiaomi, Huawei and others have extra power-saving lists; help per manufacturer: dontkillmyapp.com.
  • Which phones ring is decided by the FRITZ!Box (Telephony → Telephony Devices).

8. Alternatives

Router VPN is an option, not a requirement. The VPNs of these apps usually apply to the whole phone, so Softstringsphone and Pro also work with these:

  • MyFRITZ!App by the router manufacturer: can also open a VPN connection to the FRITZ!Box.
  • The official "WireGuard" app: import the same FRITZ!Box settings there and switch it on.
  • Without a VPN: at home on Wi-Fi, both apps call directly through the FRITZ!Box.

Only one VPN can be on at a time. If you use one of these apps, leave Router VPN off.

9. Demo video (text version)

The short demo video shows the whole flow without sound. This is what can be seen at each point. In the video – as was usual up to version 1.0.1 – all traffic goes through the tunnel, which is why the browser opens the FRITZ!Box too; with today's default "Only our apps", the browser would have to be selected for that.

TimeWhat is shown
0:00Wi-Fi off, mobile data on. Router VPN shows "No connection yet": a WireGuard VPN client for the user's own router, with no developer servers.
0:10"Add connection" → "Choose file" → wg_config.conf: the user imports the configuration generated by their own router.
0:25Switch on → disclosure "Before the VPN starts" → "Continue" → Android "Connection request" → "OK".
0:40"Connected", last answer from the router and data volume: the encrypted tunnel to the user's own router is up.
0:50In the browser, http://fritz.box opens the user's own router interface: the home network is reachable over mobile data.
1:05Back in the app, the VPN is switched off – possible at any time.

Trademarks

Router VPN and Softstringsphone are independent apps and are not affiliated with FRITZ! GmbH (formerly AVM). FRITZ!Box, FRITZ!OS and MyFRITZ! are trademarks of FRITZ! GmbH. WireGuard is a registered trademark of Jason A. Donenfeld.