OSHI vs bitchat — Bluetooth Mesh Messengers, Compared

OSHI is a free, open-source, end-to-end encrypted messenger for iOS and Android that uses Bluetooth and Wi-Fi mesh networking to send messages without Internet or cellular service. OSHI is an alternative to Bridgefy, Briar, Meshtastic and bitchat for offline communication, and to Signal for private messaging.

bitchat appeared in July 2025 and became the most talked-about mesh messenger in years: a Bluetooth Low Energy chat with "IRC vibes", no accounts, no servers, public-domain code, and an Internet fallback through Nostr relays. It is the closest thing to OSHI in spirit. This page compares the two honestly, using bitchat's iOS and Android READMEs as the source for its side of the table.

Feature comparison: OSHI vs bitchat

Sources: github.com/permissionlesstech/bitchat and bitchat-android READMEs (7 hops, Noise Protocol, geohash channels over Nostr, public domain, App Store and Play links, voice notes and images on Android), OSHI App Store listing v1.0.39, oshi-messenger.com/features/mesh-networking and github.com/Lastoneparis/OSHI.

Where bitchat genuinely wins

Fully public code. bitchat's entire iOS and Android apps are published, in the public domain, with a per-release hash manifest so you can check that the binary matches the source. OSHI publishes its cryptographic core, mesh layer and bot SDK under MIT, but not the app shell around them. If "I can build the whole app from source" is your requirement, bitchat meets it and OSHI does not yet.

Seven hops. bitchat relays across up to seven devices; OSHI relays across up to five. In a very dense crowd that is a real, if modest, difference in reach.

Zero-friction public rooms. bitchat drops you into a local mesh channel where you see everyone nearby, and its geohash channels let a whole neighbourhood or city chat when the Internet is up. OSHI is built around contacts you add by QR code, which is more private but slower to start with strangers.

Distribution. bitchat is on Google Play and on the App Store. OSHI's Android build is a direct APK download from this site.

Where OSHI is different

Wi-Fi as well as Bluetooth. OSHI uses Bluetooth Low Energy to discover peers and Wi-Fi Direct to move larger payloads, so photos, voice notes and small files travel over the mesh on both platforms. bitchat's mesh is BLE only, and its README documents images and voice notes on Android, not on iOS.

Double Ratchet for one-to-one chats. Both apps use modern cryptography. bitchat uses the Noise Protocol (X25519 + ChaCha20-Poly1305) with forward secrecy for live sessions, but its own whitepaper notes that store-and-forward messages are sealed without forward secrecy. OSHI uses X3DH and the Double Ratchet with AES-256-GCM for every one-to-one message, including ones that wait on a relay. Neither project has published a third-party audit. On OSHI's side the honest caveat is that group names and member lists are visible to its server when the Internet path is used, as its App Store listing states.

Calls, groups you control, and a bot API. OSHI has encrypted voice and video calls, private group chats, live location, view-once media, and a Python bot SDK. bitchat has no calls (Android offers push-to-talk voice in public channels) and its groups are channels rather than private member lists.

Offline maps and on-device AI. OSHI bundles downloadable OpenStreetMap regions with offline search and routing, and an assistant that runs on the device. bitchat is a chat client only.

Censorship tooling. When some Internet is available, OSHI can route through Tor and covert channels that look like ordinary HTTPS, and can hide messages in photos or text. bitchat's Internet fallback is Nostr relays, which are easy to block by domain.

OSHI does not require a phone number, email address, or account.

Range, hops and battery

Both apps ride the same radio, so their single-hop range is the same: roughly 100 m in the open, far less indoors. bitchat relays up to seven hops; OSHI up to five. Both keep messages for later delivery when the recipient is out of range. Both are subject to the same iOS background limits: a phone in your pocket with the screen off relays far less than a phone with the app open. bitchat's README describes adaptive battery modes; OSHI activates Wi-Fi Direct only while transferring data and keeps BLE in low-energy mode otherwise.

Who each app suits

Choose bitchat if you want an entirely public-domain codebase you can build yourself, open local and city-wide rooms with strangers, and the maximum hop count.

Choose OSHI if you want photos and files over the mesh on iOS and Android, encrypted calls, private groups, offline maps, on-device AI, or Tor and covert channels for when the Internet is censored rather than absent.

Frequently asked questions