A simple way to block access to the internet per app
NetGuard is an open-source Android firewall app that lets users control internet access on a per-app basis without requiring root access, making it a straightforward and flexible way to improve privacy and data usage management on mobile devices. By creating a local VPN service on the device, NetGuard intercepts and selectively blocks or allows network traffic for individual applications and addresses, supporting both Wi-Fi and mobile connections according to user preferences. ...
Personal firewall for linux desktop and android phone
...Both linux desktop and Android Phones are now supported(Front-end library and UI support)
LIMITATIONS:
Check README for details.
SOURCE:
git clone https://github.com/crs-chin/lavender.git