There is one incredibly simple solution to solve the &#x27;multi-device-problem&#x27; with security:<p>1. Allow the user to copy their keys to another device themselves.<p>To further improve security, you&#x27;d want a transfer mechanism that cannot be copied as text &#x2F; emailed &#x2F; IM&#x27;d &#x2F; whatever just so the user is discouraged from sending it in their gmail. One suitable candidate is QR codes, but without a camera &quot;Type 1 letter at a time&quot; would also work.