Don't think an app on it's own could do that, tell if a recipient has opened and read the email. It would be something that the email service itself handles. I've seen it happen with some email services, that the sender requests receipt that the email has been read, but can always decline the request and the sender gets no acknowledgment that the email was read. MS Exchange based email can do it AFAIK, but it's not universal across all email services.
There are ways to do it across all email services, like including links to zero pixel invisible GIFs on a website in the email. That's something spammers often do. If the image was viewed, then the email was opened, which is what a spammer wants to know. That the email address is valid and does get read. And so most email apps block embedded images by default.