SendinBlue is a CRM solution. With their tool, you can send emails, SMS, and even on-site chat messages seamlessly. Customers typically use their automated and transactional emails. But they've got a bunch of segmentation features that are useful as well as simple landing page build functionality.
Zendesk is a customer support tool. It's got 2 main features: ticketing and knowledge base. Ticketing: Zendesk gathers customer queries in one place where you can manage and respond to customer questions efficiently. Knowledge base allows you to create an FAQ section to guide your customers.
Trustpilot is a tool to collect reviews from customers. Those reviews are leveraged on-site to increase conversion rates or used to increase visibility with Google. Trustpilot automatically sends review invitation emails and reminders to make it easy for your customers to leave feedback.
Webflow commerce is becoming a serious competitor to Shopify. They also boast the ability to create a fully functioning website without touching code, but in addition to that - they pride themselves on giving you the ability to create unique commerce experiences for your customers.