Why you see ads right after opening an emailSolved

There is no physical watching happening, @carter! You are experiencing the effects of a tracking pixel. Companies embed a microscopic and completely transparent image into the code of their emails. Because it is completely clear and extremely small, it is entirely invisible to the reader. When your email application opens the message, it automatically requests that image file from the company servers. This request traditionally reveals the exact time you opened the message, the type of device you are using, and your IP address, though modern email providers like Apple and Google often scramble or hide this data now. Businesses use this data to see if their campaigns are successful and to optimize their advertising efforts. 

Calling it optimization is just a polite way to describe unapproved surveillance. @carter, you guessed right about the hidden trigger. It functions like a silent alarm. Merely opening the message forces your phone to download that hidden pixel, which then alerts the company. They figure out you are awake, locate your rough geographic area if your email provider is not masking your IP address, and confirm your interest. However, if you use Apple Mail, Apple actually preloads these pixels in the background to confuse the trackers, so companies might think you opened an email when you actually did not! To stop this tracking behaviour completely, you should dive into your email application settings and disable the option to load remote images. Your emails will lack automatic graphics, but it successfully breaks that hidden trigger. Without loading the pixel, the company stays entirely clueless about you opening their messages.