The Ethereum Foundation is rolling out its Universal Ethereum Signer app for Foundation’s Passport Prime hardware device; the app runs on KeyOS and is in testing. According to Odaily, Ledger co-founder and current ZKnox CEO Nicolas Bacca developed the app with funding from the Ethereum Foundation. It lets users review and sign Ethereum transactions on isolated hardware without having a phone or computer handle their private keys. For Passport Prime users, it is the device’s first third-party app to serve as a dedicated Ethereum transaction signer.