What are the services for sending e-mail with reply-to and statistics?

Question

SMTP

Good afternoon!
Please advise a service for sending e-mail messages with the following characteristics:
1. Possibility to specify reply-to;
2. The ability to conduct not mass mailings, but send one personalized message to one recipient;
3. Automatic checking of reading a letter (through a picture in html or some more complex algorithm);
4. All of the above can be done through the API.
The closest I've found is unisender.
But there is a limit of 200 letters (if you send messages without creating a mass mailing) + I did not see how to set the reply-to header.

Answer 1

mailjet