CoSign is available via TestFlight internal testing. Interested parties can send me their Apple IDs and I can invite them to the Hackathon Stakeholders group.

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  • The best way to eliminate our reliance on paper is to make the alternatives more convenient. E-signatures have come a long way, especially with novel forms of communication and user-authentication appearing more and more each day.

  • How can we utilize our existing personal devices for a more effortless e-signing experience?

What it does

CoSign is a native iOS application that uses biometrics and and near-field communication to dynamically sign and distribute electronic signature requests. It was built by one person in seven days or so.

How I built it

  • Swift + UIKit + LocalAuthentication (FaceID + TouchID) + CoreNFC + AWS iOS SDK (S3)
  • HelloSign Node.js SDK + Next.js serverless API hosted on Vercel

Challenges we ran into

  • Massive time constraints
  • Circumventing certain OAuth security mechanisms
  • I was unable to complete the App Clips functionality. It would have allowed for a third signing workflow where the user would not have to download CoSign in order to use some of its features.
  • I was unable to implement the Events API to support real-time updates. This would've been somewhat straightforward to accomplish.

Accomplishments that we're proud of

  • Completing both signing workflows (FaceID + NFC)
  • Making it somewhat pretty

What we learned

  • Good is better than perfect (this has been a very difficult lesson to learn!)

What's next for CoSign

Anything is possible

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