NetGuard is a firewall app for Android.

NetGuard provides simple and advanced ways to block access to the internet - no root required. Applications and addresses can individually be allowed or denied access to your Wi-Fi and/or mobile connection.

Blocking access to the internet can help:

- reduce your data usage

- save your battery

- increase your privacy

Features:

- Simple to use

- No root required

- 100% open source

- No calling home

- No tracking or analytics

- No advertisements

- Actively developed and supported

- Android 5.1 and later supported

- IPv4/IPv6 TCP/UDP supported

- Tethering supported

- Multiple device users supported

- Optionally allow when screen on

- Optionally block when roaming

- Optionally block system applications

- Optionally notify when an application accesses the internet

- Optionally record network usage per application per address

- Material design theme with light and dark theme

There is no other no-root firewall offering all these features.