Parity Technologies released a new version of Parity Signer, a mobile application that turns old smartphones into offline wallets.

The company announced the V3 beta on Wednesday, which will enable users to store assets, vote for governance proposals and sign transactions offline, with integrations for both the Polkadot and Ethereum blockchains.

Offline, or “air-gapped,” wallets provide the simplest form of protection from hackers and malware attacks. The company suggests that smartphones running the app be kept on airplane mode.

“To keep your funds safe, the phone containing your accounts should never be connected to the internet or even be connected to a device that is connected to the internet (such as a computer),” the company said. Users should also wipe their phones of biometric and identifying information in a factory reset prior to downloading the app.

The new version allows users to create Kusama accounts to connect with Polkadot-js apps. For all accounts, users will receive a recovery phrase and choose a “pin” to sign transactions. Transfers do not involve private keys, but instead utilize the industry standard QR code for two-way communication between hot wallets and cold signers.

The app’s code was audited during a recent overview of the entire company performed by Trail of Bits.

Parity was co-founded by former Ethereum Foundation security chief Jutta Steiner and Gavin Wood. The company develops tools for the decentralized web, including Substrate, a service that lets users create customized blockchains for decentralized applications.

In January, Parity was awarded a $5 million grant from the Ethereum Foundation.

Parity Signer photo courtesy of Parity Technologies