deBeam - Secure File Transfer

Tan Vi

In-app purchases

About this app

deBeam transfers files directly between devices over local Wi-Fi at full network speed. No cloud upload. No account. No file size limit. Your files never leave your local network.

── HOW IT WORKS ──
Pairing takes just 3 seconds:

The receiver taps "Receive" to show a QR code and a 6-digit token.

The sender scans the QR code or enters the 6-digit token.

Tap "Send" to complete.

── CROSS-PLATFORM TRANSPORT MODES ──

▶ Wi-Fi Direct (Peer-to-Peer)
No router needed. deBeam creates a direct device-to-device Wi-Fi link. The receiver becomes a Group Owner, and the sender joins directly.
• Real-world speed: 50–100 MB/s. A 1 GB video transfers in under 20 seconds.
• No router bottleneck, no bandwidth sharing with other network devices.

▶ LAN (Same Wi-Fi Network / Hotspot)
Already on the same router or connected via a Mobile Hotspot? deBeam uses your existing local network path. Every device keeps its own IP, eliminating collisions. Seamlessly transfer files between Android, iOS, iPadOS, macOS, and Windows with zero setup.

── MILITARY-GRADE NATIVE ENCRYPTION ──

Security in deBeam is implemented in C++ at the lowest native layer using Monocypher 4.0.2 for maximum performance (~500 MB/s on modern chips) and zero latency.

• Key Exchange (X25519 ECDH): Every session generates a fresh keypair from scratch using the OS secure random number generator. The receiver's public key is embedded in the QR code or derived via token entry to establish a mathematically unbreakable shared secret.
• Encryption (ChaCha20-Poly1305 AEAD): Every byte of your data is encrypted using the same protocol as TLS 1.3 and WireGuard VPN. Files stream in 1 MB chunks with unique nonces to eliminate cryptographic reuse attacks.
• Integrity Verification: Each chunk carries a 16-byte Poly1305 authentication tag. Any tampered or replayed chunk is instantly detected, terminating the connection immediately.
• Memory Security (crypto_wipe): Ephemeral private keys and session keys are wiped from memory immediately after use. Past sessions cannot be recovered even if the device is compromised later.
• Anti-MITM Protection: An 8-byte visual key fingerprint ("A1B2-C3D4...") on the screen allows instant visual verification before data moves.

── NO SERVER. NO CLOUD. NO ACCOUNT. ──

deBeam has no backend infrastructure. No signup, no login, no tracking, no telemetry. Pairing is computed entirely on-device and works 100% offline. Files travel directly from sender to receiver.

── CORE FEATURES ──

• Send multiple files, folders, or bulk media in a single session
• All file types: videos, photos, docs, archives, APKs, RAW files, and custom formats
• Works completely offline in Wi-Fi Direct mode
• No file size or bandwidth limit
• QR code pairing & 6-digit token input (seamlessly support devices without cameras like Mac mini, PC, or laptops)
• Visual key fingerprint for authenticity verification
• Files saved securely to system Downloads or custom user-defined directory
• Real-time transfer progress per file
• Full Dark mode support
• Full Android, iOS, iPadOS, macOS, and Windows cross-platform support

deBeam. Beam it.

What’s new

• New Donate screen — support deBeam with 3 tiers via in-app purchase
• Local-currency pricing powered by RevenueCat
• Highlighted security: X25519 ECDH + XChaCha20-Poly1305 encryption
• Full localization across 10 languages
• System stability & performance optimizations across iOS and Android