People use Gmail in different ways and some people use it multiple accounts, say professional and personal accounts. For people who need to access their accounts on Gmail all at the same time, Google has some news for you. You can easily log in to your multiple accounts all at the same time in the same browser window. The problem is, singing out in one account leads to an automatic sign off from all places. Also if you start a fresh browser session you will have to use your different accounts separately from different places.
The Other Route:
If you have say three accounts on Gmail and one is your primary one that you use most and other two are just secondary and you want to be able to log into all these accounts at once without typing in the login details so many times- we have a solution for you-
Email Delegation is a facility offered by Gmail wherein a person can provide access of his Gmail account to another person, say spouse, without telling them the password and this person will have read-write access to their mail and can access it by signing into their own account on Gmail. Access to all your Gmail accounts can be gained by simply enabling the Email Delegation facility.
Sign-in to one of your secondary Gmail accounts and go to Mail Settings –> Accounts –> Grant Access to your account Choose “Add another Account” and specify your primary Gmail email address here. You’ll now get a confirmation email in your primary mailbox. Accept the request and repeat these steps for all your other Gmail accounts.
That’s it. Once you sign-in to your main Gmail account, you also check all your secondary email accounts by choosing the “Switch Account” option in the upper left corner of your Gmail window. There’s absolutely no need to manually sign in to any of the other email accounts.
This feature can be used only for Gmail as of now and other products like Groups, Docs, Calendar, etc. are not included. Also, they can only allow the third party visitor to your account, an access to the mailbox that you have assigned and not other mailboxes and if your primary account gets hacked then they have all access to your Gmail account.