Open tracking
Counting opens with a tiny invisible image in the email: when it loads, the email was (probably) opened.
How this affects you
Vaartix offers open tracking, off unless you turn it on for a domain or for a single email. Each open is an email.opened event and webhook, with a machine flag for opens that most likely weren't a person: image proxies such as Gmail's, Apple Mail Privacy Protection, and fetches within seconds of sending. Even so, open counts are approximate, since many people block images. Leave tracking off for login codes and password resets: they should be as plain and trustworthy as possible.
Learn more
Vaartix is a transactional email API built in India. SPF, DKIM and a return path on your domain are set up for you, and every feature is free during the private beta.