- [chastr](https://github.com/dolu89/chastr), a mobile directed encrypted chat app written in Xamarin.
### Libraries
- [NNostr.Client](https://github.com/Kukks/NNostr), a C# Nostr library for use by clients.
- [nostr-tools](https://github.com/fiatjaf/nostr-tools), a JavaScript client that abstracts the relay management code for use by clients.
- [go-nostr](https://github.com/fiatjaf/go-nostr), a Go library that implements relay management, plus event encoding and signing utils.
- [nostr-rs](https://github.com/futurepaul/nostr-rs), a Rust implementation of the nostr protocol.
- [relayer](https://github.com/fiatjaf/relayer), a server framework for writing custom relays.
### Tools
- [nostr registry](https://codeberg.org/rsbondi/nostr-registry), a database of known relays with their uptime and NIP support tables.
- [nostr-launch](https://codeberg.org/rsbondi/nostr-launch), a tool for launching a bunch of relays and clients locally for development and testing.
- [nostr signer extension](https://github.com/fiatjaf/nos2x), browser extension for signing events on 3rd party site without sharing your private keys with them