Idk how to block certain contacts from viewing my gmail account

[Android Central Question]

I have 1 certain person who always seems to know what I’m doing, viewing using my gmail account. Ex: I was on YouTube, which is connected to my gmail, and they knew almost immediately. I’m beginning to think they have it set up in their devices to ping them when I get on. First off , is that a thing? And secondly how can I block them from seeing my activities. This person is someone that I don’t want to report for not having my permission. Only want to stop future views.

 

[B. Diddy]

Welcome to Android Central! Do you ever share your Google account with anyone? Do you often log into your Google account on a shared device and then forget to log off?

First things first -- change your Google account password to something hard to guess (i.e., don't use your birthdate, even if you've cleverly reversed the digits). And make sure you've turned on 2-factor authentication: https://www.google.com/landing/2step/