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.

Re:amaze combines email, social and mobile conversations seamlessly so your customers can reach you however they want. It integrates directly with Shopify so you can access order data instantly and edit orders, process refunds, and update customer/order data right within support conversations.

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.

Intercom is a Conversational Relationship Platform. It shows you who is using your product or website and makes it easy to personally communicate with them with targeted content, behavior-driven messages, and conversational support.

Amplitude is one of the most advanced product analytics platforms that helps teams convert, engage, and retain customers. The platform uses behavioral reports to understand users' interactions with products and provides insights to accelerate work on a real-time basis.