A safe email testing tool for staging and development, Mailtrap enables you to inspect and debug your email samples before delivering them to your customers. It helps you keep your email messages clear of spam filters and test HTML elements for compatibility with popular email clients. The Mailtrap blog also offers helpful information such as reviews of email deliverability testing tools.
Non-promotional emails, on the other hand, will be less sales-driven and timely, and more focused on building relationships and providing value to your customers. While promotional email campaigns generally tend to yield a higher click-through rate, non-promotional messages allow you to see what interests your email subscribers so you can segment accordingly. You can follow up later with more targeted messages that help to nurture your relationship with these audiences.