SSSS Mobile

Shamir's Secret Sharing Scheme for Mobile
2020 Dustin Runnells

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Support FAQ

Q: I have a question that isn't answered in the FAQ. How do I get support?
A: You may contact the author of SSSS Mobile at

Q: What is SSSS?
A: Shamir's Secret Sharing Scheme is used to secure a secret message or password by splitting it into multiple parts, called shares. These shares are later used to reconstruct the original secret.

Q: How long can a Secret Message be?
A: 128 characters.

Q: I want to split a Secret Message that is longer than 128 characters or a file, how do I do this?
A: One way to take advantage of Shamir's Secret Sharing Scheme for large messages and files might be to encrypt your message or file with PGP/GPG (or another encryption tool) and then SSSS split only the password.

Q: What is the Token field on the Split tab for?
A: The token is a short text string to prefix the generated share with. This can be a hint at what the message contents are and/or indicate the required threshold.

Q: I entered all of the shares in the Combine tab, but my message is garbled.
A: You must enter EXACTLY the number of shares specified by the Threshold when the share set was generated, no more and no less.

Q: Why can I not write my shares to an NFC tag?
A: NFC writing functionality is currently only available on the Android version of the app and only on devices that are capable of writing to NFC tags.

Q: Why can't I read a share from NFC?
A: NFC reading is not available on all Android and NFC devices.

Q: I used SSSS Mobile's split function but lost some of the generated shares and no longer have enough to meet the Threshold. How do I recover my Secret Message?
A: This is not possible. You must have exactly the required threshold to recover your Secret Message.

Q: Can I use the SSSS Mobile app offline?
A: Yes, there is no requirement to be online to use the SSSS Mobile app to Split or Combine.

Q: How do I use SSSS Mobile to protect my Bitcoin or Cryptocurrency private key?
A: First encrypt your private key with PGP or GPG's symmetric cipher option and a very strong password. Use SSSS Mobile to split the password and store your generated shares in multiple secure locations.

Q: Can I view the source to SSSS Mobile?
A: I've uplaoded the Appcelerator Titanium source to GitHub:

Q: Is SSSS Mobile compatible with any other SSSS tools?
A: Yes! See the "ssss" tool by B. Poettering. SSSS Mobile uses the ssss-js library by Gabriel Burca.