OptinMonster

OptinMonster specializes in lead capture with over 700 templates and powerful targeting rules based on visitor behavior, location, device, and referral source. It works on WordPress through a plugin or on any website via a script, and includes exit-intent triggers, countdown timers, and A/B testing built in.

The platform shines if your primary goal is growing an email list for your course. OptinMonster isn't a full funnel builder like some competitors, so you'll need to pair it with email marketing software for nurture sequences and course delivery platforms for the actual product.