10 ms·

Netguard solves this, available on the play store and F droid https://netguard.me/ https://netguard.me/

Flere-Imsaho 10mo ago
Pro tip: use the fdroid version as it allows you to set a host file to also filter ads, etc. https://github.com/M66B/NetGuard/blob/master/ADBLOCKING.md https://github.com/M66B/NetGuard/blob/master/ADBLOCKING.md
lsaferite 10mo ago
I love netguard. Some apps refuse to work without network access, but most work fine. The lack of ads is great.
n4bz0r 10mo ago
How does it work without root? Any app can just block other apps from connecting to the internet?
- jeroenhd 10mo ago
  An app can use the VPN API to intercept network traffic. This is all done with plenty of security popups (one to inform you an app is trying to register as a VPN, the another popup when it's first activated, and the while it's active there's a permanent notification that says "your connection may be monitored" with a quick button to kill the VPN). The API is supposed to let apps do things like "route intranet/corporate app traffic over a VPN, let other traffic go through", but you can just as easily use it to drop traffic destined for certain addresses (such as ad servers), or to drop all traffic for specific apps. It's also possible to make decisions like "let this app connect to the internet on wifi but not on data". It should be noted that system applications (phone OS, Google, sometimes carrier apps) can bind to specific network interfaces bypassing this API entirely. This means you can't use this API to 100% block internet access to preinstalled apps, even though apps will need to explicitly implement networking code to bypass such firewalls. It should be noted that Google doesn't really like apps abusing the VPN API like this, in past because of the massive privacy risk. Google cut a bunch of these apps from Google Play, though there's not much they can do about APKs you download from F-Droid or github.
  - n4bz0r 10mo ago
    Neat, thanks for the explanation! Given it's a "VPN", would it work alongside real VPN?
    - rjdj377dhabsn 10mo ago
      The app takes up Android's only VPN slot, but some like RethinkDNS have VPN support built-in, so you can still connect to another actual VPN.
    - jeroenhd 10mo ago
      No, not generally. A firewall app could include an OpenVPN/WireGuard/etc. client to serve both purposes, but by default you'll have a hard time getting more than one VPN app to work at the same time.
  - ignoramous 10mo ago
    > should be noted that Google doesn't really like apps abusing the VPN API like this Not really. Only apps that use the VpnService and have VPN as their core functionality can create a secure device-level tunnel to a remote server. Exceptions include apps that require a remote server for core functionality such as: - Parental control and enterprise management apps - App usage tracking - Device security apps (for example, anti-virus, mobile device management, firewall) - Network-related tools (for example, remote access) - Web browsing apps - Carrier apps that require the use of VPN functionality to provide telephony or connectivity services. https://support.google.com/googleplay/android-developer/answer/12564964?hl=en https://support.google.com/googleplay/android-developer/answ... / https://archive.vn/KY51z https://archive.vn/KY51z > It should be noted that system applications (phone OS, Google, sometimes carrier apps) can bind to specific network interfaces bypassing this API entirely Whilst this is true for Android (connectivity checks bypass VPNs, as do VoWiFi and Hotspot traffic) [0], other OSes are known to do the same thing: https://news.ycombinator.com/item?id=24838816 https://news.ycombinator.com/item?id=24838816 [0] https://github.com/celzero/rethink-app/issues/224 https://github.com/celzero/rethink-app/issues/224
    - 10mo ago
aceazzameen 10mo ago
Netguard is fantastic. I even use it on my Sony android TV to block everything except for a few streaming apps.
evilduck 10mo ago
Netguard is amazing but I'm convinced the dev is mildly colorblind and unaware of it. The color choices and even optional themes are... something.

Pro tip: use the fdroid version as it allows you to set a host file to also filter ads, etc. https://github.com/M66B/NetGuard/blob/master/ADBLOCKING.md https://github.com/M66B/NetGuard/blob/master/ADBLOCKING.md

lsaferite 10mo ago

I love netguard. Some apps refuse to work without network access, but most work fine. The lack of ads is great.

n4bz0r 10mo ago

How does it work without root? Any app can just block other apps from connecting to the internet?

jeroenhd 10mo ago
An app can use the VPN API to intercept network traffic. This is all done with plenty of security popups (one to inform you an app is trying to register as a VPN, the another popup when it's first activated, and the while it's active there's a permanent notification that says "your connection may be monitored" with a quick button to kill the VPN). The API is supposed to let apps do things like "route intranet/corporate app traffic over a VPN, let other traffic go through", but you can just as easily use it to drop traffic destined for certain addresses (such as ad servers), or to drop all traffic for specific apps. It's also possible to make decisions like "let this app connect to the internet on wifi but not on data". It should be noted that system applications (phone OS, Google, sometimes carrier apps) can bind to specific network interfaces bypassing this API entirely. This means you can't use this API to 100% block internet access to preinstalled apps, even though apps will need to explicitly implement networking code to bypass such firewalls. It should be noted that Google doesn't really like apps abusing the VPN API like this, in past because of the massive privacy risk. Google cut a bunch of these apps from Google Play, though there's not much they can do about APKs you download from F-Droid or github.
- n4bz0r 10mo ago
  Neat, thanks for the explanation! Given it's a "VPN", would it work alongside real VPN?
  - rjdj377dhabsn 10mo ago
    The app takes up Android's only VPN slot, but some like RethinkDNS have VPN support built-in, so you can still connect to another actual VPN.
  - jeroenhd 10mo ago
    No, not generally. A firewall app could include an OpenVPN/WireGuard/etc. client to serve both purposes, but by default you'll have a hard time getting more than one VPN app to work at the same time.
- ignoramous 10mo ago
  > should be noted that Google doesn't really like apps abusing the VPN API like this Not really. Only apps that use the VpnService and have VPN as their core functionality can create a secure device-level tunnel to a remote server. Exceptions include apps that require a remote server for core functionality such as: - Parental control and enterprise management apps - App usage tracking - Device security apps (for example, anti-virus, mobile device management, firewall) - Network-related tools (for example, remote access) - Web browsing apps - Carrier apps that require the use of VPN functionality to provide telephony or connectivity services. https://support.google.com/googleplay/android-developer/answer/12564964?hl=en https://support.google.com/googleplay/android-developer/answ... / https://archive.vn/KY51z https://archive.vn/KY51z > It should be noted that system applications (phone OS, Google, sometimes carrier apps) can bind to specific network interfaces bypassing this API entirely Whilst this is true for Android (connectivity checks bypass VPNs, as do VoWiFi and Hotspot traffic) [0], other OSes are known to do the same thing: https://news.ycombinator.com/item?id=24838816 https://news.ycombinator.com/item?id=24838816 [0] https://github.com/celzero/rethink-app/issues/224 https://github.com/celzero/rethink-app/issues/224
  - 10mo ago

aceazzameen 10mo ago

Netguard is fantastic. I even use it on my Sony android TV to block everything except for a few streaming apps.

evilduck 10mo ago

Netguard is amazing but I'm convinced the dev is mildly colorblind and unaware of it. The color choices and even optional themes are... something.