Google tests out new login that replaces your password for your phone
Tuesday, December 22, 2015 at 7:44PM 
Google has started limited testing of its new password-free login feature. It made its first appearance when the Marshmallow API was unveiled at Google I/O this year. According to reddit user named Rohit Paul, the new feature would need a compatible device like the Nexus 6P. You have to authorize your phone to log into your account. And then when you sign into your Google account on your computer, you type in your email and then you’ll get a message on your phone to allow the login. If you hit yes, the computer will log into your Google account without you having to input a password. It works similar to how two-factor authentication does except you don’t have to input a code into your PC when you receive a notification on your phone.
Source: Reddit | Via: Cult of Android