OptinMonster - OptinMonster helps to convert abandoning website visitors into subscribers and customers.
Freebiebucket - Curated free tools & resources for makers 🛠
Poptin - Create engaging and high converting website pop ups and contact forms in minutes. With Poptin, you get access to a feature-packed conversion rate optimization toolkit that converts more website visitors into email subscribers, leads, and customers.
GetSiteControl - Website popup builder & email marketing suite for ecommerce
Yeps! - All-in-one bar for your website
Sumo - Free tools to grow your email list.