Comparing wordpress opt in plugin vs optinmonster

OptinMonster provides a lot of customization options. One of its most powerful features is its Exit Intent technology. It detects when a user is about to leave your website and will cause a popup to appear just before they would leave. Aside from exit-intent, OptinMonster also has trigger options based on time on page, location on the website, manual clicks on images and links, as well as referrer source such as search engine, social, favorite website, etc.

This is a free opt-in plugin from the Wordpress community that provides a high level of customization. It is not as easy to integrate as the other tools, but its free and has good community support. It provides all the standard opt-in features and integrates with a variety of email marketing solutions.