Google combines Sign in with Google and One Tap into a single identity SDK

Google has consolidated several of its identity and authentication APIs under a single software development kit (SDK) called Google Identity Services.

The new SDK features existing APIs including the Sign in with Google button, which will be familiar to millions of developers and consumers the world over for enabling easy sign-ins and user authentication across web and mobile apps. However, the SDK also includes the lesser known One Tap API, which is a cross-platform sign-in and sign-up mechanism that constitutes an  authentication prompt that may appear anywhere on a website or app.

Google actually first announced One Tap for the web back in 2017, and following various iterations and feedback phases the company teased the all-new One Tap for web and Android last year, alongside the new consolidated SDK. This latest announcement is all about pushing these identity APIs under the same roof, and showcasing One Tap for more developers.

Authenticate

One Tap is an authentication module that prompts users to sign up or sign in wherever they are on a website or app. It means that if a user clicks a link to visit a specific page on a website, for example, they may be presented with a prompt that slides down from the top-right hand side on a desktop website, or up from the bottom on a mobile device.

Relying on secure tokens rather than passwords, users can then sign in or sign up on the spot, without having to create an account or remember any previous credentials they used to sign up. And crucially, they’re not redirected to a sign-up / sign-in page which may disrupt their flow and ultimately cause them to ditch their session altogether. Moreover, if a user signs in on a web page using One Tap, it applies the same authentication status across platforms — including Android devices.

Above: Google’s One Tap

It’s worth noting that the One Tap sign-in prompt isn’t exclusively for those who wish to use their Google credentials to access a website or app. If the user has previously registered an email / password combination and saved it in Chrome, Android autofill, or Smart Lock for Passwords (on Android), they will be presented with those options too.

Above: One Tap: Multi-account sign-in

Ultimately, it’s all about removing friction, enhancing retention and acquisition, and reducing churn. Users don’t have to remember what email address or password they used previously to access an online service, or even whether they have registered at all. And because the One Tap prompts slides into the user’s current view, they don’t have to navigate back to whatever page it was they were on before a redirect.