Google Smart Lock is the latest technique for user authentication.
How Google Smart Lock Works
This new authentication API authenticates users through a centralized service. That means you don’t need to enter your IDs and passwords for every app. For example, Netflix. This has led to a considerable decrease in support issues regarding login. Also since it works on Chrome as well, it can be of great ease when you use Chromebook.
For Those Who Have Multiple Accounts
If you have different accounts for personal, work and etc., then you can select which account you want to use for Smart Lock for each app.
Some enhancements have been announced by Google. Both developers and users will be benefited by these. Soon we can expect passwords to be not used at all. Authentication will soon become that easy.