More than ever before, Android apps for mobile devices are now interconnected. Many of them have built-in ad networks, analytics, and other user tracking tools. Installing a firewall app will provide users more control over such applications and restrict their capacity to communicate with the outside world and engage in "phoning home" activities. Here's how to do it.
Limit Network Access of Android Apps to Protect Privacy
Some programs take advantage of the innocent and unwitting end user. Popular messaging programs such as Facebook, Instagram, WhatsApp, Viber, and others track your approximate location: are you at home, on the go, at school, at work... Every few minutes, they transmit tracking requests and other analytics data to Amazon AWS, Google Cloud, and other 3rd party computing platforms, to mention a few. They know a lot more than you realize or are ready to admit. What's the most surprising part? Users have no idea how much they're being followed (and exploited) in this manner!
If Google chose to, they could restrict the monitoring activities of any app – at least as an option. What exactly do we mean by this? For example, an app could only transmit tracking, analytics, and other data to its servers when it is being utilized — for example, as a front-screen activity. To support near-real-time communication, messaging and communication applications would be permitted to receive push alerts. Other programs, such as shopping portals (Amazon, eBay, AliExpress, and so on), games, and non-critical "offline" utilities, should be kept away from continuous tracking misuse until they're in focus.
You may mimic "no internet connection" mode for select programs using a firewall app, while all other apps and services have full internet access. This is especially important for security concerns, such as if you are concerned that a certain software, such as a File Manager software, which may save sensitive information such as your FTP server or NAS disk password, may “leak” the information to an unauthorized third party.
To block any Android app spying activities, you may use a firewall tool, such as NoRoot Firewall, which is one of the best ad-free firewall program for Android OS! There are a couple more that are just as wonderful, each with its own set of features, so try them all and see which one best suits your requirements and productivity.
The image above is from NoRoot Firewall, and it shows how many frequent requests (sometimes known as "phoning home") the famous ES File Explorer used to make during startup and normal usage. We don't know what sort of traffic it is, but we can reasonably presume it's ad-serving networks (from which applications draw external embedded content), banners, promotions, and sending user data and crash reports back to developers.
With a firewall program, you can prevent all of this! Of course, without root access on Android, firewalls will use a less appealing bogus (redirect) VPN connection, which may interfere with the functionality of other apps or cause minor glitches (e.g. ERR NETWORK CHANGED in an older Chrome mobile browser app, which now works fine), but this is usually completely harmless.
It's important to remember that bypass filters are required for programs like File Managers and any other software that needs local network access!
NOTE: By default, the Firewall software will block all network traffic. Unless you set bypass rules and provide them unfettered network access, your games may stop operating correctly, and you will be unable to play online team games, earn free coins and lives, and do other things. At the very least, when using Wi-Fi, you must allow network access. Depending on your phone operator and mobile data package, you may either disable or enable access when on Mobile Data.
How To Install Firewall App For Android
Go to the Google Play Store and search for "firewall". There are tons of apps but to demonstrate we are using NoRoot Firewall app.
It is simple to install and use. Accept the permissions and connect to the VPN (required on non-rooted devices only). By default, it will become active immediately and block anything. Configure the program to run every time the system starts up / boots up, and set any custom rules you want.
How To Define Custom Rules / Filters and Configure Firewall App For Android
NoRoot Firewall makes it simple to create filters (custom rules), and the software lets you combine or mix rules for Mobile Data and Wi-Fi independently.
The key is to enable local network traffic (for example, 192.168.*.*:*, where the section following the IPv4 address and colon (:) symbol is the port wildcard). Local network traffic is normally secure, and it restricts device access to the same Wi-Fi network as the one to which your device is now connected (e.g. your home Wireless Router). This way, the app will be able to access printers, other devices, PCs, network storage drives, smart TVs, and other devices in your house or workplace, but it will be banned from accessing anything else.
The NoRoot Firewall app will detect each new program's intent to access the network (local or distant, it doesn't matter) and block it by default, unless you explicitly allow it or set additional rules / filters for each program. For example, you may need to accept the IP address 192.168.*.* and choose a predetermined * (wildcard symbol) from a drop-down box for the port.
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| Credit: tehnoblog |
In a different definition, you may block any other IP address. Other restricted and private ranges, such as 10.*.*.* and 172.16.*.*, may be bypassed if necessary. Everything else should therefore be automatically blocked if you don't use or require it.