Securely signing in to Google
If you're signing in to your Google Account from a device that only you use (for example, a personal laptop), we recommend leaving the "Stay signed in" checkbox selected. This ensures that you won’t be constantly interrupted to re-enter your password and makes your future sign-ins easier with Account Chooser.
For shared devices (a computer at an Internet cafe, for example), we still recommend that you leave the checkbox selected, but here are our recommendations to ensure you sign in securely:
Devices used by lots of people
Examples: Computers at libraries or internet cafes
Public computers, if well-maintained, automatically clear a user’s web history and cookies. If you’re unsure, we recommend that you use the private browsing feature of the browser. If private browsing isn’t available, clear the browser’s history, cache, and cookies before and after you use the device.
Devices shared with a few people
Examples: Family computer
If you plan to use the device briefly, such as when visiting a friend or relative, we strongly suggest using the private browsing, if it’s available.
If you plan to use the device on an ongoing basis (say, for example, it’s your family computer), then we suggest creating a user profile either in the operating system or in the browser so you can keep your information private from other users. We recommend you leave the "Stay signed in" checkbox selected to take advantage of Account Chooser and longer sessions. Learn how to add user profiles on an Android device or in Chrome.
If none of these security options are available to you, we strongly suggest you do not sign in to your Google Account. If you do sign in, we recommend deselecting the "Stay signed in" checkbox in case you forget to sign out.