The joy of Streak, and the fact that they work remotely, 
   is that I could see them forwarding my email to each other.

   You’ll see in the map below that it was opened in multiple 
   locations, multiple times.

   It’s like sending a text to someone you’re interested in 
   after a date, and knowing that they’re talking to their 
   friends about how to respond. They’re interested.
 
   This doesn’t always work obviously, but it gave me a ton of 
   confidence in the moment.

Interesting... Tracking people opening your app. I assume this tracking using a hidden image in the email?