AFWall+

AFWall+ is an Android application that controls which installed applications are allowed to send and receive network traffic. It presents a list of the applications on the device, each of which can be permitted or denied access separately for mobile data, Wi-Fi and other connection types, so that a given application may be reachable on one network and cut off on another.

Rules are applied at the level of the system's own packet filter rather than by intercepting traffic in a virtual private network, which means AFWall+ requires root access on the device to install and update those rules. This also means it works alongside a VPN connection rather than competing with it, but it cannot be used on a device where root access is unavailable.

The application is published by portgenix under the GPL-3.0-only licence and runs on Android only. Its interface is centred on the per-application rule list, with rules taking effect when applied rather than requiring a reboot.