Klaviyo is a marketing automation and customer data platform built mainly for ecommerce and retail brands. It combines email, SMS, segmentation, predictive analytics, forms, and revenue reporting so marketers can send campaigns based on customer behavior rather than broad lists.
The platform works well when a store has enough customer data to make segmentation and automation valuable. Small lists can start cheaply, but brands need to model pricing carefully because costs rise with active profiles and messaging volume.