Best Offline Messenger Apps in 2026 — OSHI, Briar, Bridgefy, Meshtastic, bitchat

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. This page compares all five on the facts, with sources, and says which one fits which situation.

An "offline messenger" is an app that delivers messages when there is no Internet and no cellular service, by passing them directly between nearby devices — usually over Bluetooth, sometimes over Wi-Fi Direct or a LoRa radio. Five apps dominate the category in 2026: Briar, Bridgefy, Meshtastic, bitchat and OSHI. (FireChat, the app that made the idea famous in 2014, was shut down in 2020; Berty is promising but its authors still describe it as not ready for sensitive use.) There is no single winner: the right one depends on distance, on who else has the app, and on what you need to send.

The comparison table

Sources: each app's own documentation — briarproject.org, bridgefy.me/app, meshtastic.org docs, the bitchat READMEs — plus the 2022 Albrecht/Eikenberg/Paterson paper on Bridgefy, the OSHI App Store listing (v1.0.39), oshi-messenger.com/features/mesh-networking and github.com/Lastoneparis/OSHI. "Not verified" means the vendor's documentation did not let us confirm it.

OSHI

OSHI forms a mesh from the phones themselves: Bluetooth Low Energy for discovery and short messages, Wi-Fi Direct for photos, voice notes and files, and up to five store-and-forward hops between phones. One-to-one chats and calls use X3DH and the Double Ratchet with AES-256-GCM. OSHI does not require a phone number, email address, or account. It also bundles offline OpenStreetMap maps with routing and an on-device AI assistant, and when some Internet is available it adds Tor and covert channels. The honest limits: about 100 m per hop in the open, phones need the app open to relay, group names and member lists are visible to the OSHI server when the Internet path is used, only the cryptographic core and mesh layer are published (MIT), the Android build is a direct APK rather than a Play listing, and there is no public third-party audit yet.

Briar

Briar is the pioneer and the most trusted name here. It is fully open source (GPLv3), independently audited by Cure53, and syncs messages between contacts over Bluetooth, Wi-Fi or Tor with no server at all. It is recommended by Privacy Guides. Its limits are equally clear: it is Android-only (with a desktop beta), and its offline mode syncs directly between people who are already contacts rather than relaying across a crowd of strangers. If everyone in your group runs Android and you value audit history above features, Briar is the safe choice. See OSHI vs Briar.

Bridgefy

Bridgefy has the biggest install base, is on both app stores, and offers a public Broadcast mode that reaches every Bridgefy user nearby. It relays across other users' phones over Bluetooth at about 100 m per hop. Its weaknesses are on the trust side: it is closed source, it was shown to be unencrypted in 2020, and researchers reported that its 2020 Signal Protocol implementation still had flaws in 2022. Bridgefy's own instructions also say you need Internet the first time you open the app. Good for reach; weaker for verifiable privacy. See OSHI vs Bridgefy.

Meshtastic

Meshtastic is not a phone app in the usual sense; it is GPL-3.0 firmware for cheap LoRa radios, with an app that acts as the keyboard. In exchange for carrying a radio you get kilometres of range per hop (2–5 km typical, far more with elevation), multi-day battery, position sharing and up to seven hops. Messages are short text only, channel encryption uses a shared key, and the project's own docs say it is not as secure as Signal. Unbeatable for distance; irrelevant if you cannot hand everyone a radio. See OSHI vs Meshtastic.

bitchat

bitchat is the newest of the five and the most transparent: the complete iOS and Android apps are in the public domain, with hash manifests per release. It is a Bluetooth Low Energy mesh with up to seven hops, Noise Protocol encryption for private messages, public local channels, and geohash "location channels" over Nostr when the Internet is up. It has no calls, no Wi-Fi transport, no maps, and its store-and-forward messages lack forward secrecy. Ideal for open rooms with strangers and for people who want to build the whole app from source. See OSHI vs bitchat.

Which one for which use case

A festival, stadium or protest

You need a phone-only mesh with multi-hop relay and no sign-up. OSHI, bitchat and Bridgefy all qualify. Pick OSHI if you want to send photos and voice notes and have a mixed iPhone/Android group; pick bitchat for open public rooms; pick Bridgefy if you are betting on strangers already having it installed. See OSHI for festivals.

Hiking, sailing, off-grid land

Distance wins. If everyone can carry a LoRa radio, Meshtastic. If not, OSHI keeps a group in touch within a few hundred metres and gives you offline maps and routing for the walk itself; an optional OSHI LoRa node extends the mesh by kilometres. See OSHI for hiking.

An Internet shutdown or heavy censorship

Locally, any phone mesh works. The difference is what happens when a little Internet returns: Briar and OSHI can route through Tor; OSHI adds covert channels and steganography. Bridgefy needs Internet for first setup, and bitchat's online fallback (Nostr relays) is easy to block. See the Internet shutdown survival guide.

Disaster response and emergencies

Combine two: a phone mesh (OSHI or bitchat) for the people on the ground, and Meshtastic radios for the kilometre-scale links between sites. OSHI's offline maps and live location help here. See OSHI for emergencies.

Journalists and sources

Audit history matters most. Briar (audited, Android-only) is the conservative choice; OSHI adds iOS, no phone number, Tor and covert channels but has no public audit yet. See OSHI for journalists.

Maximum verifiability

Briar (GPLv3, audited), Meshtastic (GPL-3.0) and bitchat (public domain) publish everything. Berty does too. OSHI publishes its cryptographic core, mesh layer and bot SDK but not its app shell; Bridgefy publishes nothing.

What no offline messenger can do

None of these apps works alone. A mesh needs other people running the same app within radio range, and a Bluetooth hop is a hundred metres at best. None will reach someone in another city with no Internet anywhere in between. None can protect a message on a phone that is unlocked and seized. Choose the app your group will actually install before the day you need it, test it once in airplane mode, and keep a second one as a fallback — the two apps' meshes do not talk to each other.

Frequently asked questions