ClickSend is a cloud-based messaging platform tailored to small and midsize businesses. They provide a comprehensive solution to send, track and manage business communication. Thanks.io, on the other hand, is a customer relationship management (CRM) platform which helps businesses manage recipient lists, segmentation, and automated follow up emails. The key difference between the two platforms is that ClickSend focuses on sending one-off messages, whereas Thanks.io is designed to facilitate long-term relationships with customers. Thanks.io allows for personalized customer engagement through segmentation, automated journeys and context-sensitive messages whereas ClickSend focuses on providing users with a comprehensive system for managing business communication.