WatchPDF vs deBeam

PDF app for Apple Watch only View PDF files by inserting them into your Apple Watch. You can check PDF files anytime, anywhere on your Apple Watch. The watch app can be run alone, but To send PDF files to Apple Watch, you need the iPhone app. Please make sure you have an Apple Watch before purchasing the app. The iPhone app does not support viewing PDF files. The iPhone app sends PDF files to a connected Apple Watch. *Features* - Device: Apple Watch (WatchOS 10+), iPhone (iOS 17+) - File: PDF - Zoom in and out: Zoom in and out of content using the zoom in/zoom out buttons. - Page mode: Switch pages back and forth and go to a specific page - Vertical mode: Navigate pages by scrolling up and down in the list - Support for password-locked PDFs - Runs alone on Apple Watch, iPhone app required for file transfer - Touch the content screen to hide and display various menus and buttons - App screen brightness - App Lock: Only possible when the watch is password-protected ** Phone Streaming ** - Browse and open files inside nearby iPhone app from paired Apple Watch app, and switch pages - Access, browse, and open files on your iPhone from your watch without transferring them to your watch - Paired iPhone and Apple Watch must be in close proximity, and install and run the app on iPhone - Page quality will be adjusted. ** Search "WatchPDF" on YouTube to watch a usage video. ** Our app does not provide separate PDF files. PDF files can be viewed by inserting the file stored by the app user into the app.

deBeam transfers files directly between devices over local Wi-Fi at full network speed. --- HOW IT WORKS --- Pairing takes just 3 seconds. The receiver taps "Receive" to show a QR code. The sender scans it and taps "Send". Done. No usernames, no pairing codes, no waiting for cloud servers. --- WIRELESS TRANSPORT MODE --- Wi-Fi LAN (Same 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 IP collisions. Fully cross-platform: transfer between iOS, iPadOS, macOS, and other mobile or desktop platforms with no setup required. Real-world speed: 50-100 MB/s. A 1 GB video transfers in under 20 seconds. High-performance local streaming without routing bottlenecks or cloud dependency. --- PROTOCOL-LEVEL END-TO-END ENCRYPTION --- Security in deBeam is the protocol itself, implemented at the lowest native layer. Key Exchange - X25519 ECDH Every session generates a new keypair from scratch using random bytes from the OS secure random number generator. The receiver's public key is embedded in the QR code. Scanning performs an X25519 Elliptic Curve Diffie-Hellman exchange, producing a shared secret that exists only on those two devices for that one session. The attacker space is 2^255 - computationally impossible to brute force. Key Derivation - BLAKE2b The shared secret is processed through BLAKE2b with the context string "deBeam-v3-session". This binds the derived key strictly to this protocol version, preventing key reuse or replay attacks. Encryption - ChaCha20-Poly1305 (AEAD) Every byte of your files is encrypted with ChaCha20-Poly1305. Files stream in 1 MB chunks, each with a unique nonce derived from its file index and chunk position. No nonce reuse: No two chunks ever share a nonce - cryptographic reuse attacks are impossible. Integrity: Each chunk carries a 16-byte Poly1305 authentication tag. Any tampered or replayed chunk is instantly detected and the connection terminates. Memory Security - crypto_wipe() After the key exchange, ephemeral private keys and session keys are immediately wiped from memory using crypto_wipe(). Past sessions cannot be recovered even if the device is compromised later. Threat Coverage Eavesdropping: Blocked by ChaCha20-Poly1305 encryption. Man-in-the-middle: Blocked by X25519 (cannot forge secret without private keys). Rogue device: Impossible without the QR-embedded public key. Brute force: 2^255 key space - mathematically infeasible. An 8-byte visual key fingerprint ("A1B2-C3D4...") on the receiver's screen allows quick visual verification before files move. --- NATIVE PERFORMANCE --- The encryption and streaming engine is written via native integration using Monocypher 4.0.2 - a compact, audited crypto library. ChaCha20-Poly1305 runs at ~500 MB/s on ARMv8. Encryption overhead is zero compared to Wi-Fi throughput - no speed penalty for maximum security. --- NO SERVER. NO CLOUD. NO ACCOUNT. --- deBeam has no backend infrastructure. No signup, no login, no tracking, no telemetry. QR pairing is computed entirely on-device and works 100% offline. Files travel directly from sender to receiver. --- CORE FEATURES --- Send multiple files in a single session All file types: videos, photos, docs, archives, RAW files, and custom formats Persistent local storage - chosen destination saved securely via Security-scoped Bookmarks No file size limit QR code pairing - no manual IP entry, no accounts Visual key fingerprint for authenticity verification Files saved securely to system Downloads or custom user-defined directory Real-time transfer progress per file Full cross-platform support across mobile and desktop devices deBeam. Beam it. Privacy Policy: https://devitan-docs.gitbook.io/devitans-apps/x.-privacy-policy-for-devitans-apps Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/