Keychat’s browser is simply the WebView component that comes with the OS.
I get Keychat is trying to be like the WeChat of Bitcoin and Nostr, but the browser thing doesn't move me and I turn it off. Not a technical criticism, I am just very conservative with my keys. I'd prefer a bunker like Amber and a separate messenger/wallet and browser or even all three separate that work seamlessly with one another.
With what I mentioned about Session, see:
https://soatok.blog/2025/01/14/dont-use-session-signal-fork/
Follow up after response to it: https://soatok.blog/2025/01/20/session-round-2/
Discussion
I looked into this in our public project chat rooms and said it is a plus. GrapheneOS users benefit from running Keychat in GrapheneOS than anywhere else since we harden the webview other apps use. It works in favor for users of both