Rogue

SendGrid provides and manages an email server on your company's behalf, so your communications with customers are reliably sent and delivered as needed. It's perfect when you need to send transactional emails, password recovery emails or notifications to users from your website.

Affirm boasts that it can boost the average order value (AOV) customers spend when they’re shopping at your store by giving them a way to purchase your products with credit, but at a (potentially) lower cost than they would with a credit card.

With Mailchimp you can send newsletters and automated emails. You can build your email list with form or import your known contacts. Mailchimp offers pre-designed email templates and a drag and drop email builder.

RudderStack is an open-source customer-data platform that provides a holistic view of the customer. From there, activate your customer data in 200+ destination apps like Google Ads, Customer.io, Mailchimp, Segment many more.

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.