Vanadium is a privacy and security enhanced fork of Chromium for GrapheneOS. Vanadium provides the WebView and standard user-facing browser on GrapheneOS. It depends on hardening in other GrapheneOS repositories and doesn't include patches not relevant to the build targets used on GrapheneOS. Vanadium isn't yet officially available for users outside GrapheneOS, although they plan to do that eventually. It won't be able to provide the WebView outside GrapheneOS and will have missing hardening and other features. More information can be found on the GrapheneOS features page.
Brave for Android is a Chromium-based browser. It includes it's own content blocker ("Brave Shields") which is essentially a Rust version of uBlock Origin. It's not particularly focused on security and does add a lot of unnecessary features (attack surface) such as a cryptocurrency wallet and their scheme to try and replace ads.
Brave uses the anti-competitive Play Integrity API to make certain features exclusive to Google certified operating systems. They don't provide official support for using it without Google Play even though Chromium does with certain features missing. They could use the hardware attestation API instead to provide support for more than Google certified operating systems:
GrapheneOS unsuccessfully tried to convince them to officially support not having Google Play without success so they didn't ask about this.
Despite this, Brave remains the best option for GrapheneOS users when Vanadium doesn't meet their needs (doesn't currently have as good content filtering as Brave). Brave is far from perfect but certainly much less bad than most other options, especially the Gecko-based ones (Firefox, etc.).
- Google Play
- Obtainium (via GitHub)