Wallet apps have continued to develop and evolve since Ethereum released in 2014. More and more good-designed and user-friendly wallets have been created, like imToken, Mist, Parity, etc. It’s easier for users to utilize wallet apps than before. But few people keep secure concerns in mind, such as the offline signing of transactions, as it always means hard and tedious operations.

For now, we are proud to announce that imToken 1.2.0 fully supports the offline signing of transactions with just three steps. (Edit: …also imToken 2.0 😁)

Why we support it?

The centralize exchanges are honeypot to the hackers, there were quite a lot breach happened each year. To avoid the lost, it suggests user to store their crypto currency into wallets, and the most secure wallet is cold wallet, like hardware wallet or offline wallet(airgapped). For offline wallet its quit inconvenient to sign the transactions. Imagine that, you need a USB disk to copy data from one to another computer/device, mostly twice. Because you have to prepare the transaction params on the hot wallet, then transport to the cold wallet for transaction data siging by private key. And then transport the signed data back to hot wallet for broadcasting the transaction.

Is it necessary to send every transaction like this way? For security reasons, we say yes, but for convenience, probably not. It cloud be easier to do the pairing offline signing via mobile phones. So we did it.

Let’s see how the offline signing works in imToken 1.2.0.

Prepare:

- Two phones installing the imToken.

- One is online just watch wallet without private key imported, called hot wallet.

- The another is offline has private key imported, called cold wallet.

Step1:

Inputs transaction params into the hot wallet transfer from and generates a transaction QR-Code.

Step2:

Cold wallet scans the transaction QR code for authorizing to sign and generates the signed data QR-Code.

Step3:

Finally, hot wallet scans the signed data QR-Code then send transaction, done!

Amazing! Find one of your retired cellphones, put it offline and install imToken, that’s the cold wallet which can protect your assets the most secure way.