Stack Duo by Cypher Stack vs Keycard Pal

Stack Duo is a fully open source cryptocurrency wallet. It's a stripped down version of Stack Wallet that only has Bitcoin and Monero. With an easy to use user interface and quick and speedy transactions, this wallet is ideal for anyone no matter how much they know about the cryptocurrency space. The app is actively maintained to provide new user friendly features. Highlights include: Bitcoin and Monero included All private keys and seeds stay on device and are never shared. Easy backup and restore feature to save all the information that's important to you. Custom address book Favorite wallets with fast syncing Custom Nodes. Open source software.

Keycard Pal is an open-source, air-gapped companion app for the Keycard hardware wallet. Your private keys live on a PIN-protected NFC smartcard. They never touch your phone and never touch the internet. HOW IT WORKS Your software wallet shows a transaction as an animated QR code. Scan it with Keycard Pal, review every detail on screen, then approve by holding your Keycard to your iPhone. The signature comes back as a QR code for your wallet to scan. No network pairing, no cloud, no accounts. REVIEW BEFORE YOU SIGN - Full decode of Ethereum transactions: transfers, ERC-20 sends and approvals, contract calls - EIP-712 typed data review, including a permit view that warns about unlimited token approvals - Bitcoin PSBT review with inputs, outputs, fees and change detection - Optional transaction simulation and ENS name resolution WORKS WITH YOUR WALLET Connect with animated UR QR codes or WalletConnect. Export accounts to Ledger Live, Bitget, Bitcoin multisig coordinators and any UR-compatible wallet. YOUR KEYS, YOUR CARD - Generate a 12 or 24 word recovery phrase with an optional passphrase - SLIP-39 share backups - PIN management with an optional scrambled keypad - Manage pairing slots, card name and factory reset OPEN SOURCE The full source code is on GitHub under the MIT license. Read it, file issues, or contribute. A Keycard is required for signing. Without one you can explore the app, but signing, key generation and address export need the card.