Google continues to take steps to improve the security of Android, and the latest addition starts to roll out today. Lengthily referred to as "Android notifications for newly added devices," the feature does exactly what you would expect it to do.
Whenever a new device is added to an account, a native Android notification will appear. This gives users the opportunity to review the device and determine whether it is something suspicious.
If the notification should appear at a time when a user has not knowingly signed into their account with another device, the Review Account Activity option comes into play. Just like reviewing Google account activity online, this reveals more about the sign-in event such as the type of device, the IP address, and where the login took place.
Two options are present: "Yes, that was me", and "No, secure account". Google says it believes the new notification system will be far more effective than what came before: "Now users are quickly notified on multiple devices when a new device has been added. This increases transparency to the user of what actions they've performed and allows them to flag any suspicious activity they may be seeing on the device. We’ve also found that with Android notifications, users are up to four times as likely to review the information as compared to email notifications."
The feature is rolling out to all Android users starting today, and the rollout is expected to take a few weeks to complete.