Keycard Shell

Cold Storage

Keycard Shell is a fully open-source hardware wallet from the Keycard project, using modular NFC smart cards as interchangeable secure elements. All transaction signing happens inside the secure element chip; the device communicates with software only via QR codes (air-gapped). Released in 2025, it features a replaceable battery, duress PIN for plausible deniability, and completely public hardware schematics, firmware, and Java Card applet under MIT license.

Details

Type: smart_card
Notes: Keycard Shell — NFC hardware wallet based on JavaCard smart card
Price: €109
Battery: Yes
Interface: NFC card
Price Usd: 99
Air Gapped: No
Device Type: hardware_wallet
Form Factor: Credit card (NFC only)
Open Source: Yes
Screen Type: TFT
Bitcoin Only: No
Connectivity: NFC
Manufacturer: Status (open source)
Release Year: 2025
Secure Element: Yes

Links

github

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