How to stop Email Tracking in Gmail Mobile App (Android and iOS)
To stop email tracking in the Gmail mobile app, tap the hamburger menu at the top-left corner.
Scroll down and select “Settings” from the options.
Choose the email account you want to disable tracking pixels on
Scroll down until you find the “Images” option, now tap on it.
Choose the “Ask before displaying external images” radio button, and you are all set.
Now the Gmail app will no longer display images by default to protect you from hidden email trackers.