sounds like it can replace Briar?

An offline, serverless mesh messenger for Android — end-to-end encrypted, no internet, no accounts, no Google Play services.

Your phones talk directly to each other over Wi-Fi Aware and Bluetooth LE, and relay for one another hop by hop.

https://f-droid.org/en/packages/app.getknit.knit/
https://github.com/getknit/knit