Really surprised to see SendInBlue on AppSumo - https://appsumo.com/products/sendinblue-lifetime/
Sendinblue is an established and mature Automation platform that allows you to create beautiful email campaigns, custom landing pages, signup forms, automated workflows, transactional messaging, CRM, and more.
There are two plans on AppSumo, one is a lifetime deal for $79 :
Other is annual plan with three options: