What I like most about Apollo.io is it lets you find your target audience. The tool also helps you find verified contact details, apart from allowing you to send bulk emails to people you're looking to contact.
The most valuable feature of the solution is the intent data it provides our company. I find it really interesting how Apollo.io can detect the intent of companies looking for your company's solution.
What's missing in Apollo.io is a proper CRM and pipeline management system. The tool is excellent at finding contact information, but it has room for improvement in sending emails and tracking the sales pipeline.
Apollo.io still needs to work on the CRM part because it has started building some CRM infrastructure for companies to use and track their sales activities.