Most marketing emails contain a single pixel hidden in the email which tracks you. This pixel calls home, lets the marketers/spammers know that you opened the email, and begins tracking your movement through their system.
Here is how to block it within Outlook on your IOS device (ipad, iphone, etc)
Click on the File
Open Trust Center
Click on Trust Center Settings
Find Automatic Download
Place check mark in:
Don’t download pictures automatically in standard html…..
Don’t download pictures in encrypted or signed…..
Thats it! Tracking pixel disabled