Key Shopify PDP CRO Principles

  1. Sticky Add-to-Cart Bar on Mobile: Display a fixed bottom bar with variant options and an ATC button when the main button scrolls out of view.
  2. High-Velocity Image Swatches: Preload image assets so selecting a variant option updates the main gallery instantly without loading spinners.
  3. Transparent Delivery Estimates: Render dynamic delivery estimate dates (e.g. “Order in 2 hrs for delivery by Thursday, Aug 15”) near the ATC button.
  4. Social Proof & Reviews: Display star rating summaries near the title linking directly to customer review sections.

Developer Takeaway

Variant Image Preloading: In Shopify Liquid themes, generate JSON data structures containing variant image URLs so JavaScript variant swatches switch images synchronously on option selection.