Casa

Firmware version B-2.0 (BTC-Only) or newer allows you to use Casa V 3.6.0 or newer with your Keystone Essential or Pro hardware wallets.‌ Detailed instructions provided below explains how to directly interact with Casa to create a 2-out-of-3 multi-signature wallet between your Keystone hardware wallet, Casa's Mobile Key and Casa's Recovery Key as the 3 participant co-signers. This tutorial also explains how to execute a 2-out-of-3 multisig transaction.

I. Preparation

1. Setup your Keystone Essential or Pro. (Getting started in 5 steps)

2. Firmware versions B-2.0 (BTC-Only) or newer running on Keystone Essential or Pro.

(Please read How to upgrade firmware for more details.)

3. A Smartphone with Casa V3.6.0 or newer downloaded and logged in with your Casa account.

(Tips: Smartphone requires iOS 14.1 or up and Android 6.0 or up.)

4. A MicroSD card (FAT32 format with capacity NOT exceeding 512GB).

(How to Format a MicroSD Card to FAT32?)

II. Creating a 2/3 multisig wallet on Casa

1. Run the Casa V3.6.0 or newer on your smartphone and log into your Casa account.

2. Go to the “BASIC MULTSIG” interface and select [Begin Basic Multisig Setup] > [I Understand] to enter the page so you can create a 2/3 multi-signature wallet. Then, select [Set Up Mobile Key] > [Continue] to successfully add Casa's mobile key as the first multi-signature participant.

3. Turn your Keystone hardware wallet on.

4. Select the [Menu] icon > [Multisig Wallet] > then select [Casa Mode] > [CONFIRM] > [Continue] > [Continue, It’s Ready]. Your Keystone hardware wallet will display a QR code to pair with Casa.

5. In the Casa app: select [Set Up Hardware Key] > then select [Keystone] > [Continue] > [Continue, It’s Set Up]

6. Select [Continue], then use your smartphone's camera to scan the QR code displayed on your Keystone. Your Keystone hardware wallet should now be successfully added as the second multi-signature participant.

7. Select [Set Up Recovery Key] and set the security questions to add the third multi-signature participant. Doing so would complete the creation of your 2/3 multisig wallet. (please be advised that this Casa recovery key feature is available in the Casa security plans from the gold or above.) You can now begin making multisig transactions at this point.

III. Receiving bitcoin to your 2/3 multisig address

1. Go to the Casa multisig wallet and select [Receive] to display your receiving address (please be advised this address is a "nested segwit" address, and not a Legacy and Native SegWit address). Please copy the address provided or scan the QR code for it.

VI. Sending a 2/3 multisig transaction

1. Create a 2/3 multisig transaction on Casa

1) Open the Casa app on your smartphone to enter your multisig wallet.

2) Select [Send] to open the remittance interface.

3) Configure the desired amount, then select [Choose Recipient] to input the receiving address by scanning the provided QR code or entering the address. You can also set the transaction fee as well.

4) Check all the transaction details before swiping up to confirm. The Mobile Key will begin signing the transaction automatically once you've swiped upwards. Select [Continue Signing] when the first signature is added.

2. Sign multisig transaction with Keystone

1) Select [Tap to add a new signature] > [Sign with Keystone Instead]. Casa will display the unsigned transaction information in a dynamic QR code format.

2) On your Keystone hardware wallet: Select [Multisig Wallet] > [Casa Mode], then select the [scan] icon and scan the QR code displayed on Casa.

3) Select [Sign] > verify your transaction with your password or fingerprint > then press [Confirm] to show the signed transaction data in QR code format.

4) Back on Casa: Select [Continue, It’s Scanned], then scan the QR code displayed on your Keystone to transmit the signed transaction data.

3. Broadcasting Transactions with Casa

1) Select [Complete Transaction] to broadcast the transaction.