gluble

Connect with the people around you. Chat, share photos and discover what's happening nearby — no internet required.

Gluble is a Bluetooth group messaging app for situations where Wi-Fi or mobile data are unavailable or impractical — music festivals with overloaded networks, conferences and meetups, sports stadiums, hiking trips, sailing, or any busy venue where the signal drops.

HOW IT WORKS

Phones near each other discover one another over Bluetooth Low Energy and exchange messages directly, without going through the internet or any server. Each phone keeps its own cryptographic keypair locally in the iOS Keychain so messages can be signed and verified between the people you are talking with.

KEY FEATURES

• End-to-end encrypted: Direct messages and private channels are sealed with AES-256-GCM. Photos travel inside the encrypted payload, never as plaintext. Every packet is signed with Ed25519 so recipients can verify who sent it.
• Bluetooth-only: Device-to-device communication. No outbound HTTP requests to third parties. No location tracking. No analytics. No ads.
• Public hashtag channels and private channels: Join open conversations by hashtag, or create a private channel for your group protected by a 10-character access code with Argon2id key derivation.
• Identity verification: Verify any contact face-to-face by scanning their QR code, so you know exactly who you are talking to.
• Block users: You can block any sender; their messages will no longer appear on your device.
• Proof-of-work anti-spam: Every message requires solving a small cryptographic challenge (SHA-256 leading zeros), which makes mass spam computationally expensive on the local mesh.
• Photo attachments: Attach images to your messages, encrypted in private channels and direct messages.
• Local message history: The last 50 messages per channel are cached for 8 hours on nearby devices, so people who arrive a bit late can still see the context.

USE CASES

• Music festivals and large events: coordinate with your group when the cellular network is overloaded.
• Conferences and meetups: keep your team coordinated during sessions.
• Stadiums and venues: a private channel for the venue's daily menu, fan chat in real time.
• Outdoor activities (hiking, sailing, camping): communicate with your group when there is no coverage.
• Travel: keep your travel group connected across an unfamiliar city.
• Weddings: Create a private channel and share the code with guests. Nobody gives their name,number or email. Enable auto photo-save and every image shared in the channel.

PRIVACY

Gluble does not use email, phone number, or any personal data. Each phone generates an Ed25519 and X25519 keypair on first launch and stores it locally in the iOS Keychain. There is no central server, no cloud account, and no public profile — a technical consequence of the offline Bluetooth architecture.