Can I hide the Read Receipt image?
The short answer is no -- you will not be able to request a read receipt or track clicks without the Read Receipt image.
Read on for some our thinking for how we've implemented the feature:
Read Receipts vs. Open Tracking
There are two approaches we could have taken – read receipts vs open tracking. Open tracking hides a transparent one-pixel image (about the size of a period) somewhere in the message. When someone opens the email, open tracking notifies the sender of the exact time the message was opened and provides the IP address of the computer that opened the message. If you’re out of town, all a tech-savvy burglar needs to do is have you open one of their spyware-laden messages and see that the location of your IP address is in a different country. Or, more commonly, an aggressive salesperson can call you or send you a follow-up saying that he noticed you read his email 32 seconds after 9:28 this morning. Creeptastic!
Read receipts are different, because they respect the recipient’s privacy. The recipient sees an explicit notification and has an opportunity to choose not to provide a read receipt. We also do not collect the recipient’s IP address, location, or the exact minute someone opened the email. Unlike read receipts in Outlook, however, Boomerang defaults to providing the read receipt — the recipient must explicitly choose not to do so.
Even more important, our early data shows that including a read receipt in an email you send out may increase the chances that you’ll get a response to your message. Try doing that with open tracking!