Klaviyo is the best in class email marketing solution for eCommerce. It's powerful because it connects to your store, and you can create awesome customer segments based on past purchasing behaviors, customer preferences, and even future predictions of spending.

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.

Shopify is a commerce platform that allows anyone to set up an online store and sell their products. It's the go-to eCommerce platform for young direct-to-consumer brands. It's ease of use and setup is what's most attractive to merchants, but also the incredibly vast Shopify app store.

WooCommerce is a free WordPress plugin that adds e-commerce functionality to your WordPress website so you can have an online store. With just a few clicks, your WordPress website turns into a fully-functional e-commerce website.

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.