n of m Shamir's Secret Sharing

n of m splits your Ethereum seed phrase into distributed shares using Shamir's Secret Sharing — a cryptographic method where any n shares out of m total can reconstruct your secret, but fewer than n reveal nothing. Generate a BIP39 mnemonic, choose your threshold (e.g., 3-of-5), and export printable QR code cards. Store cards in separate secure locations. When you need your wallet back, scan enough cards and the app reconstructs your seed phrase on-device. No servers. No network calls. No analytics. No telemetry. Everything happens on your device. GENERATE SEED PHRASES • Create 12, 15, 18, 21, or 24-word BIP39 mnemonics • Three entropy sources: system cryptographic RNG, device accelerometer motion, or both combined • Import and validate existing seed phrases with BIP39 checksum verification SPLIT INTO SHARES • Configure any threshold: need n shares out of m total (up to 10 shares) • Information-theoretic security — fewer than n shares reveal zero information • Optional PIN encryption before splitting (SHA-256 key derivation) • Optional BIP39 passphrase for separate derivation trees PRINTABLE QR CODE CARDS • Export each share as a full-page PDF card • Clear labels: share number, threshold, creation date, instructions • Derived Ethereum address printed for verification • Distribute via system share sheet or save to device SCAN AND RECOVER • Camera-based QR scanner with real-time validation • Automatic duplicate detection and secret ID matching • Progress indicator shows how many shares remain • PIN and passphrase prompts when configured • Recovered mnemonic displayed with derived addresses ENCRYPTED VAULT • On-device storage backed by iOS Keychain and Secure Enclave • Per-secret locking — independently lock each entry • View and copy Ethereum addresses, reveal private keys • Re-derive addresses or re-export PDF cards anytime • Editable names, metadata, and notes HD WALLET DERIVATION • MetaMask path (m/44'/60'/0'/0/i) • Ledger Live path (m/44'/60'/i'/0/0) • Custom BIP32/BIP44 paths for advanced users • Derive multiple addresses from a single mnemonic SECURITY • Fully offline — zero network requests of any kind • FaceID and TouchID authentication for vault access • Optional 4-8 digit PIN with 10,000-round SHA-256 key derivation • BIP39 passphrase support for hidden wallet trees • Shamir's Secret Sharing over GF(256) provides unconditional security LEARN • Visual guide explaining Shamir's Secret Sharing • Mathematics deep-dive: polynomial construction, Lagrange interpolation, finite field arithmetic • Walkthrough of threshold concepts and distribution strategies Built for cryptocurrency holders who take self-custody seriously. Whether you manage a personal Ethereum wallet or implement geographic redundancy for cold storage, n of m gives you cryptographic splitting without trusting anyone else with your keys.