YSK · Cold Wallet Simulator · v1.1.0

Cold Wallet Simulator

Simulate hardware wallets on a phone for development and interoperability testing—do not hold real assets. Short name CWS. Version 1.1.0 (build 6). Package hk.ysk.cws.

Google Play App Store coming soon GitHub Licence

Android · hk.ysk.cws
1.1.0 · build 6
Proprietary

CWS Proxy: phone connected, Ledger Nano X, virtual HID up

1.1.0Build 6

Google PlayAndroid is live

Not a secure elementDo not hold real assets

A simulator for development and interoperability testing

CWS runs on a physical phone and speaks the vendor protocol as a Bluetooth peripheral. It is not a secure element, and it is not endorsed by Ledger, Trezor, or OneKey. Do not hold real digital assets in this software.

InstallGoogle Play · Android
Pick a modelLedger / Trezor / OneKey
Store a secretBIP39 / SLIP-39
LinkBluetooth, or USB HID via Proxy
TestDerive, sign, QR export

Simulate selected Ledger / Trezor / OneKey models (Bluetooth)

The phone speaks the vendor protocol so a third-party wallet can treat it as that model. OneKey Mini has no Bluetooth radio and is not simulated.

BIP39 / SLIP-39 secrets in OS secure storage

The secret stays in operating-system secure storage. That is not a secure element, and it is not absolute safety.

CWS Proxy presents the phone as USB HID (desktop wallet link)

The desktop proxy presents the connected phone as USB HID so a desktop wallet can link. macOS is coming soon. Ubuntu and Windows: coming soon / build from source.

QR air-gap export of accounts / descriptors (seed export needs confirm)

Accounts and descriptors can leave by QR. Exporting the seed requires confirmation on the phone.

Multi-chain derivation and signing (see README chain list)

Derivation and signing cover the chains in the README. Opening an app name does not mean every host screen for that chain is finished.

Seeds are not absolutely safe — see security notes

Read the security notes before you generate or import a secret. Treat every secret entered here as unfit for any purpose that matters.

Item	Fact
Name	Cold Wallet Simulator (CWS) · 冷錢包模擬器
Version	1.1.0 (build 6). GitHub has no Release tag yet.
Package	`hk.ysk.cws`
Purpose	Development and interoperability testing. Do not hold real assets.
Licence	Proprietary / all rights reserved (YSK Limited). Source is published for audit. Not MIT.
Android	Google Play
iOS	Coming soon. This page has no App Store link.
CWS Proxy	macOS coming soon (HID not approved). Ubuntu / Windows: coming soon / build from source. No download URL.

Selected models over Bluetooth

The phone is a Bluetooth peripheral. The table is the published model set. This software is not endorsed by those brands. Ledger Live’s genuine-device check is not expected to pass.

Brand	Models	Phone transport
Ledger	Nano X, Flex, Stax, Nano Gen5	BLE APDU
Trezor	Safe 7	BLE THP
OneKey	Classic, Classic 1s, Pure, Touch, Pro (V1); Pro 2, Neo (V2)	BLE protobuf

Not simulated

OneKey Mini has no Bluetooth radio and is not simulated.
BLE advertising does not work in a simulator or in Expo Go. A physical phone is required.
CWS is not Ledger Live, Trezor Suite, or the OneKey app.

Other transports

USB HID: CWS Proxy presents the phone to a desktop wallet.
Trezor Bridge: the proxy can answer compatible hosts on local port 21325.
QR: UR and BBQr for accounts, descriptors, and a seed export after confirmation.

Seeds are not absolutely safe

BIP39 or SLIP-39 secrets sit in OS secure storage. CWS has no secure element. Do not put a seed that controls real digital assets on the device. The full statement is in the security notes and the README.

What the software does

A new secret comes from the operating-system CSPRNG. The mnemonic and SLIP-39 shares are shown so they can be written down. They are not written to the clipboard.
The stored value is entropy (or the SLIP-39 secret) with WHEN_UNLOCKED_THIS_DEVICE_ONLY. A passphrase stays in memory for the session.
A release build asks the OS authenticator before a secret is revealed, imported, saved, or applied as a passphrase, and again before a signature or a backup-seed QR.
Android release sets FLAG_SECURE on secret screens. iOS blurs the app switcher. iOS does not black the live image.

What stays open, on purpose

A connected host can derive addresses without a further prompt. That is not the seed. Assume the host can list accounts.
The proxy does not filter APDUs. A site you connect in Chrome can send any command the phone already implements.
A signature and a seed export still wait for the phone. Listing addresses and exporting an extended public key stay silent, because compatible wallets list accounts that way.
Anyone who can unlock the phone, debug the process, photograph the screen, or connect a host can reach more than the UI admits.

Known usability gaps in 1.1.0: Phantom may not complete unlock after connect; Rabby’s camera may fail to scan the phone QR in some setups; Core may not list Avalanche X and P accounts end to end; OKX may not show asset balances for an imported account. Those gaps are not a reason to treat this software as a place to hold assets.

CWS Proxy presents the phone as USB HID

A desktop wallet links over virtual USB HID. Signing still happens on the phone. This page has no download URL for a macOS, Ubuntu, or Windows package.

Platform	Status
macOS	Coming soon. Mac App Store HID is not approved. No download link.
Ubuntu	Coming soon / build from source. No download URL.
Windows	Coming soon / build from source. No download URL.

What the proxy does

It forwards HID reports to the phone over Bluetooth so a desktop wallet sees a USB device.
It can answer Trezor-compatible hosts on local port 21325.
It does not filter APDUs. A WebHID client you already allowed on this machine can send commands the phone implements.
Build steps are in the GitHub repository README. That repository has no Release tag for this version, and this page does not ship an installer.

The screenshots below are the CWS Proxy 1.1.0 UI. They are not download buttons.

QR air-gap, plus multi-chain derivation and signing

Account keys and output descriptors can be exported as UR or BBQr. A backup-seed QR requires confirmation on the phone. The chain list is the README’s.

Air-gap export

Export accounts and descriptors without handing the seed to the desktop.
Seed export needs confirm. A release build also asks the OS authenticator.
Whether a host can scan depends on the format. Documented hosts include Rabby, MetaMask, Sparrow, BlueWallet, and OKX.

Signing

Signing a transaction or message waits for press-and-hold on the phone.
Listing addresses and exporting an extended public key stay silent so compatible wallets can finish account listing.
While the phone is advertising, the device screen says a connected host can derive addresses.

README chain list	Coverage
Bitcoin	Legacy, nested SegWit, native SegWit, Taproot
Account chains	Ethereum and EVM-style paths, Avalanche, Solana (Ledger and Phantom paths), Cosmos, Tron, XRP, Cardano, Polkadot, TON, Aptos, Sui, NEAR, Litecoin, Dogecoin, Stellar, Tezos, and BNB Beacon

A Ledger app catalog is included so a host can open an app name. Opening a name does not mean every host screen for that chain is finished. The chain list is in the README.

Proprietary. Source published for audit.

Cold Wallet Simulator is published by YSK Limited. The licence is proprietary, all rights reserved. The source is in a public repository so you can audit the implementation. It is not MIT and it is not an open-source licence. GitHub has no Release tag for 1.1.0. Do not treat the repository URL as an installer.

Android is live

The Google Play app is the public download today.

Package hk.ysk.cws
Version 1.1.0 (build 6)
Development and interoperability testing only

Downloads that are not here

These have no link, so the page does not point at a missing file.

iOS App Store: coming soon
CWS Proxy for macOS: coming soon (HID not approved)
Ubuntu / Windows: coming soon / build from source

Google Play App Store coming soon Source (for audit)

Questions: WhatsApp +852 6160 4242 or [email protected]. No prices on this page, and no proxy installer.

Frequently asked questions

Can Cold Wallet Simulator hold real assets?

Direct answer: No. It is a simulator for development and interoperability testing. It is not a secure element, and it is not endorsed by Ledger, Trezor, or OneKey. Do not hold real assets.

Is Cold Wallet Simulator open source or MIT?

Where do I download Cold Wallet Simulator?

Direct answer: Android is on Google Play (hk.ysk.cws). The iOS App Store listing is coming soon. This page has no App Store link. GitHub has no Release tag for this version.

How do I get CWS Proxy?

Direct answer: macOS is coming soon (Mac App Store HID is not approved). Ubuntu and Windows are coming soon, or build from source. This page has no proxy download URL.

Are seeds absolutely safe?

Direct answer: No. BIP39 or SLIP-39 secrets sit in OS secure storage, and seeds are not absolutely safe. See the security notes.

Which hardware models does it simulate?

Direct answer: Selected Ledger, Trezor, and OneKey models over Bluetooth. OneKey Mini has no Bluetooth radio and is not simulated. The model list is on this page and in the README.