Recently I have been getting few enquires “Why a firewall is needed for an Android?“. But the question is quite relevant as it sounds unusual for an end user which makes them think that Android is vulnerable. I would like to clarify those facts regarding the usage of firewall in Android.
As you all know Android is one of the popular mobile platform available today. Since the popularity of android is increasing day by day because of its open source nature and unrestricted application development. Hence the rate of applications published in the android is increasing at a faster rate. As applications are large in number the quality and trustworthiness of the application is a big question. So installing an application can often be risky at times. Because an end user except techy guys seldom notice the list of permissions that are displayed before the installation begins. So an untrusted application can perform malicious activity by stealing data and passing to the hacker via internet. In order to prevent this firewall is necessary for blocking such applications connecting to internet.
And another one aspect of have a firewall is to control the data usage. These devices are completely Internet depended. They require internet for services such as email, social networking, news, weather and lots more. But in order to make use of these services completely one need to have an unlimited data plan. If the data plan is limited then these services will consume all the data in the given data limit and finally end up in paying extra cost for each additional usage. So the firewall application has provison to block particular application installed in the device from making connection to INTERNET.
Now further a question arises why we need ROOT access to perform all these operation. All the firewall applications available uses netfilter iptables binary that is the core part of Linux kernel which is responsible for packet filtering process. I have explained in my previous posts regarding netfilter iptables. The device should have root access in order to manipulate the iptables in android.