As we know, many operating systems like windows, linux, mac os, etc contains a built-in firewall that allow the user to set his own rules, unfortunately android system doen't have a built-in firewall, for that we need a third-party application to perform a firewall rules like the other systems that we mentioned, Droid firewall come up to solve this problem.
Droid Firewall allow you to set your own firewall rules almost like the other systems, which means you will be able to perform inbound and outbound rules, and block any address or port number from using the network.

Droid Firewall uses VpnService:
VpnService is necessary (and the only way) to catch the traffic so that the app can process the packets and determine which packet is allowed to pass and which packet should be blocked depends on the rules applied.
Although vpn service is required, your data is not shared outside the application or accessed by anyone, respecting the user's privacy policy.

We hope you have an enjoyable experience with our application, and if you have any inquiries or would like to get in touch with us for any reason, please feel free to contact us through our official email.