Online Document Vaults
No single tool is appropriate for all tasks. Please consider your requirements and select accordingly. For long term, completely offline, robust, and user friendly storage of valuable static secrets, Entropy is generally the better choice.
Apple Family Passwords
Apple Family Passwords is a recently added feature to Safari on macOS Sonoma where you may share website login details with family members. Each family member has the ability to use, add, or edit passwords. It appears to be a handy solution for sharing access to low value data, like your Netflix, Kindle, and so on. It is not currently well suited to sharing high value offline data, where access is undesirable until after your death or incapacitation.
SLIP-0039 is only suitable for reconstructing a supported cryptocurrency wallet. The encryption scheme is based on a four round fiestel network. Entropy can be used to reconstruct any secret, including any cryptocurrency wallet that uses the standard BIP wordlist. Entropy is designed with great care for ease of use, even for people who may not be well versed in technical matters. Do your loved ones or associates understand the difference between the SLIP derivation paths m/44'/501'/0'/0' and m/44'/60'/0'/0/1? If SLIP-0039 suits your use case then please consider it but in our view, for most people Entropy is a more robust and user friendly solution.
Any Online Secure Document Vault
A more secure alternative to any online vault might be to configure your existing Apple ID with a Legacy Contact, then encrypt the data you upload to iCloud with a secure passphrase using any number of 3rd party tools that run locally on your computer. Once encrypted and uploaded, use Entropy to create and distribute shares of your encryption passphrase. Configuring iCloud with Legacy Access in this way enforces a logical and physical seperation between your data, the encryption key, and the encryption process. This way you ensure there is no single point outside of your control capable of fully accessing your secured information.
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