NFC HARDWARE WALLET · QUIET BY DESIGN

Security,
without the spotlight.

Keep security inside the card and ease in everyday life. RiverKey explores independent signing hardware in the shape of an ordinary membership card: no conspicuous crypto branding, and no extra device to carry.

A discreet card format · Designed for everyday life

85.6 × 54 mmStandard card size · Design target
NFCTap interaction · Design direction
0 batteriesPassive power · Design target

01 / THE CENTRAL IDEA

Security doesn't need to announce itself.

Many hardware wallets protect what matters, but make the person carrying them easier to notice. We are exploring a different approach: keep protection within, and let the exterior feel ordinary.

TRADITIONAL DEVICES / THE USUAL WAY

Easy to recognize

A distinct shape, screen, and ports can reveal a device's purpose at a glance, even when its internal safeguards are strong.

INSIDE / PROPOSED DESIGN

Keep signing inside the card

The design proposes a separate secure element as the signing boundary, with sensitive operations kept within the card rather than exposing private keys to an external interface.

OUTSIDE / VISUAL LANGUAGE

Nothing to give it away

No coin motifs, flashing lights, or obvious gadget silhouette. At first glance, it is simply part of everyday life.

02 / A SIMPLE ROUTINE

From setup
to everyday ease.

Keep each interaction simple and let the card's design handle the complex work. The proposed flow will evolve through product development and independent security review.

01

Set up the card

The proposed experience begins with card and companion-app setup. The security process still requires independent evaluation.

02

Tap your phone

Use your phone's NFC connection to access public account information while keeping sensitive material out of the external interface.

03

Confirm the action

Signing is intended to stay inside the card. This website does not initiate or process transactions.

04

Carry on

Put the card away and continue your day. It need not look or feel like another piece of technology to carry.

03 / DESIGN PRINCIPLES

Less to show.
More to consider.

Every detail serves two goals: make the card feel at home in daily life, and make its security boundaries clearer. Final specifications depend on validation.

01 / CONTACTLESS

Tap with NFC

A familiar contactless interaction is the design direction, reducing the need for extra cables or readers.

02 / CARD FORMAT

A familiar size

A standard card format is the target, designed to fit the wallets and cardholders people already use.

03 / MATERIAL

Understated materials

Everyday membership cards inspire the feel and visual language, rather than an overtly technical aesthetic.

04 / DURABILITY

Made for daily life

Durability and long-term use remain priorities for prototype evaluation; final materials and test results are not yet confirmed.

05 / PORTABILITY

Nothing extra to carry

The card is intended to fit naturally among the essentials you already bring with you.

06 / FOCUS

Only what matters

Fewer exposed controls and unnecessary interfaces keep the experience focused on what matters most.

CURRENT PHASE / PRODUCT DEVELOPMENT

The next everyday card
is taking shape.

The product is currently in the prototype stage. Its appearance, interactions, technical specifications, and availability may change. Final details will be confirmed at launch. Purchases and wallet functions are not currently available.

IN
PROGRESS
2026 / PRODUCT DESIGN

04 / PEOPLE WE'D LIKE TO MEET

Better products begin with honest conversations.

An early idea needs more than applause. It benefits from questions, observation, and collaboration across different perspectives.

01

Security researchers

Help examine the threat model, interaction boundaries, and risks that might otherwise be overlooked.

02

Content creators

Help discuss new hardware formats and real-world use cases with clarity and care.

03

Experienced users

Bring practical self-custody experience and questions about carrying a device every day.

05 / GET IN TOUCH

Let's start
a conversation.

If understated hardware design interests you, email us about product direction, security research, or real-world experience.

HARDWARE CARD · OPEN TO IDEAS
ProjectHardware Card
Current stagePrototype development
CollaborationSecurity research / User feedback / Content partnerships

A great first email

Introduce yourself, share the design question that interests you, and tell us how you would like to collaborate. Use the button below to copy our email address.