The latest TestFlight version of nthKey works with Specter Desktop (a Python application that runs on top of Bitcoin Core to make multi-sig super easy).
The app displays a QR code, which you scan with Specter. Then you select which devices make up your multisig wallet, pick a threshold, and you're all set.
Signing a transaction is also as simple as scanning a QR code, clicking Sign and then scanning the result with Specter.
Give it a try (on testnet)!
Stephan Snigirev dropped by @stephanlivera's podcast recently to discuss his DIY hardware wallet as well as the Specter Desktop application. They mention how QR scanning can be a pain if your webcam isn't very good, which I've experienced too. Part of the problem is that web applications don't process QR as efficiently as native code (e.g. on a Mac try QR Journal). Fortunately the app has some other sharing options too; I still need to implement outbound air drop.
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