Building The Best One Click Sign In
Tags: oneclicksignin, authentication, passwordless
Published: 2020-06-03 11:35:56

**Abstract: One click sign in using device authentication offers convenience and security to the user.**

One click sign in allows users to authenticate in just one click.  Delivering this was the reason DID.app was started. This is our story of implementing one click sign in.

## Why do we need one click sign in?

Users have ‘account creation fatigue’. The average person already has 150+ accounts and the problem is still getting worse. There are so many websites that want you to create an account and it's hard to keep track of them all.

Users want to engage but without filling in endless forms.  We also know users crave passwordless experiences by the rapid growth of password managers both in and out of the browser.  Password managers simulate a passwordless sign in but only serve to paper over the root of the problem.  They are cumbersome to set up a very desirable target for hackers.

## How does one click sign in work?

Single factor authentication can relies on either: [something you know, something you have or something you are](https://did.app/articles/the-three-factors-of-authentication).  In a typical username and password setup, the user relies on something only they know (their password) to prove their identity.  For one click sign in, we rely on something nearly ever user already has with them, their personal devices. 

The user authenticates by proving they have access to a specific device. If the device is present, the user is authenticated.  This is achieved with a simple cryptographic transaction between DID.app and the user’s device initiated by a single click.

Users should be familiar with this type of authentication. It works on the same principle as using as a key to unlock your front door or using debit card to pay for something.  These are both forms of authentication that rely on something the users has (a key or a debit card) and are used multiple times every day.

DID.app's One Click Sign In works using cryptography.  A key pair generated and stored by the device are challenged by DID.app to prove identity.  The user actually has to have access to the physical device for One Click Sign In to work.  Users can set up multiple devices if they regularly use more than one device.  This greatly reduces the threat of account theft because hacking is only economical on scale and without actually having to steal a person's handbag.
## Speed, Security and Safeguards

DID.app is focused on fast, simple and secure authentication.

Most devices today are already valuable to their owners. Most are protected by passcodes or biometric protection like fingerprint scanning or facial recognition. Devices are rarely far from their owners for long. And if one is lost DID.app makes it easy to remotely revoke the permissions the device had. 

By comparison, passwords are vulnerable to phishing, guesswork and brute force.  Social media accounts secured with passwords fall victim to the same threat and even some text messaging based MFA has weaknesses given that sim cards can be cloned.

No solution is perfect but device authentication is the least scalable form of account theft simply by virtue of the fact the hacker must have access to an unlocked physical device.

Finally, the best solutions recognise when a fallback may be needed.  On the rare occasion the user wants to use a shared computer to access their account, One Click Sign In is not possible so DID.app falls back to [magic links](https://did.app/articles/building-the-best-magic-link).

## One Click Sign In Goes Hand in Hand With Conversions

One click sign in is all about convenience.  Users hate creating accounts, it’s not rocket science. What’s there to love about coming up with a new password or endlessly forgetting which social network you used to sign in last time?

Convenience for the user equals conversions for your website.  If you’re authenticating at all, you are looking for user engagement.  Users turning away at sign up isn’t great use of marketing spend. No solution will ever induce a 100% conversion rate but One Click Sign In can help cut your losses.

There is perhaps a more pressing point than conversions.  One Click Sign In is also about being respectful of your user’s time and giving them the best possible customer service experience you can muster.

Happy customers are usually easier to work with.  The genuine convenience of One Click Sign In gives users a truly frictionless authentication experience.  Users end up in a much better frame of mind than if they’d been sent round the houses on a whistlestop tour of their inbox, your password reset pages and back to the sign in page again.  

If you would like to find out more about the technical inner workings of DID, read our [‘How DID Works’](https://did.app/articles/how-did-works) page.  If you have any questions about one click sign in, please email us: [team@did.app](mailto:team@did.app)