BitBox02 (Shift Crypto)

Swiss hardware wallet. Two devices as of September 2026 — the original BitBox02 and the BitBox02 Nova — each in two firmware editions:

• Multi: BTC + altcoins.
• Bitcoin-Only: BTC, ETH disabled (smaller attack surface).

Hardware

Original BitBox02, per the bitbox.swiss specifications as of September 2026:

• USB-C connector. No Bluetooth, no NFC.
• Touch sliders (capacitive touch sensors) for input.
• Display: 128x64 px white OLED.
• Dual chip: ATSAMD51J20A microcontroller (120 MHz Cortex-M4F, TRNG) running the open-source firmware, plus an ATECC608B secure chip over I2C. The firmware stays outside the secure chip so it does not have to be trusted blindly.
• microSD slot (for backup).

BitBox02 Nova

Announced 20 June 2025, shipping since summer 2025. The original BitBox02 stays in the lineup and keeps receiving firmware updates; Nova is a second model, not a replacement. Same Multi / Bitcoin-Only edition split, same microSD backup, passphrase and anti-klepto.

Differences from the original (bitbox.swiss specs, September 2026):

• Secure chip: Infineon OPTIGA Trust M V3, EAL6+ certified and NDA-free (documentation readable without signing an NDA). Same dual-chip split. It also enforces the 10-failed-password factory reset with a hardware counter, where the original enforced that limit in firmware only.
• MCU: unchanged — both spec pages list ATSAMD51J20A. The 20 June 2025 announcement cites increased storage capacity on the device for future firmware features, without naming the component.
• Display: 128x64 px white OLED under a tempered glass top.
• Connectivity: USB-C plus Bluetooth Low Energy. Still no NFC.
• iPhone / iPad: first BitBox usable with the BitBoxApp on iOS 16+ / iPadOS 16+; USB-A and Lightning adapters ship in the box. Bluetooth exists only because USB is restricted on those platforms.
• Colors: Midnight Black, Polar White, Bitcoin Orange.

Firmware source has two secure-chip backends (ATECC* and OPTIGA* error spaces in src/securechip/securechip.h), so integrations that parse device errors must handle both.

Whisper (Nova's Bluetooth architecture)

Bluetooth is treated as untrusted transport:

• Runs on a separate DA14531 MCU with its own open-source firmware, no access to the main MCU's flash and no wallet secrets.
• That firmware is loaded into the Bluetooth chip's RAM on every boot and cryptographically verified by the main MCU — no mutable state.
• BLE LE Secure Connections with authenticated pairing (matching code shown on device and in the app), and the existing BitBox end-to-end encryption still runs on top, so the Bluetooth chip cannot read transaction data.
• Random private addresses (RPA) and the lowest viable signal strength while advertising — pairing only works in close vicinity.
• USB first: once data arrives over USB the Bluetooth chip is shut down; if USB is already connected when the app starts, the Bluetooth firmware never runs. Bluetooth can also be disabled persistently in firmware (re-enabling then requires a USB host).

Full design write-up: Whisper (Shift Crypto, 3 July 2025).

Backup

• 24-word BIP39 seed.
• Backup also written to microSD (encrypted with device password).
• Restore: insert microSD + enter password.

App

BitBoxApp — desktop / mobile. Direct wallet interface plus device-management.

API

JavaScript: @bitbox-mobile/api. Python: bitbox-bridge.

Third-party: Sparrow, Specter, HWI, Electrum.

HWI added BitBox02 Nova support in 3.2.0 (10 February 2026); older HWI releases only enumerate the original BitBox02.

Compared

Common issues

• microSD insertion: backup-encrypted SD card must be inserted for restore; devices ship with one.
• Slider input has learning curve vs touchscreen.
• App vs HWI: some flows easier in BitBoxApp; HWI works for generic integration.

See also

• trezor/SKILL.md
• coldcard/SKILL.md
• hwi/SKILL.md