Mobile-ready hero images could lift Black Friday sales by up to 29 percent; Supreme Court weighs tariff refunds

E-commerce sellers heading into the holiday season are being urged to optimize their main product images for mobile screens, with research suggesting the fix can lift sales by 20 to 29 percent.

A 2022 study by Unilever and Cambridge University found that so-called Mobile Ready Hero Images significantly increase mobile conversions by making key product details instantly visible on small phone screens. The stakes are high: mobile commerce now accounts for 65.7 percent of all global e-commerce sales.

Mobile shoppers frequently add items to their cart straight from thumbnail views without ever opening the listing. Standard product photos become illegible on phones, leaving shoppers unable to see flavor, size or variant details, causing misorders, returns and abandoned carts. More than 46 percent of shoppers cannot pick out critical information from poorly optimized thumbnails.

The recommended approach is a 4Ws framework. A hero image must instantly communicate who the brand is, what the product type is, which specific variant is shown, and how much is included, such as 500ml or a three-pack.

Images should pass three tests. First, visual clarity: text and numerals must stay legible at thumbnail size, using a squint test, and Unilever now requires all images to pass a formal clarity check before going live. Second, color contrast: contrast should score above 60, or at minimum above 45, which matters for the roughly 8 percent of men and 0.5 percent of women with color vision deficiency. Third, a clean background: pure white, with no shadows, reflections, floating text or graphics breaking the pack edges, and only a small black size lozenge permitted in the bottom right corner.

Practical steps include enlarging on-pack text two to three times beyond its physical size, removing clutter such as barcodes and busy backgrounds, zooming so the product fills at least 80 percent of the frame, and adding a bold size badge. Sellers are advised to test images at 200 by 200 pixels before uploading.

During Black Friday and Cyber Monday, mobile traffic surges and shoppers make split-second decisions. When one thumbnail clearly shows the variant, pack size and volume and a competitor's does not, the clearer image wins the click even at a higher price. Unilever tested more than 30,000 images against this framework, and Amazon's own brands use the same approach.

In other news, the US Supreme Court heard arguments on whether the president overstepped his authority by imposing sweeping tariffs of 10 to 50 percent on goods from nearly every country, invoking a 1977 emergency powers law on the grounds that the trade deficit posed an extraordinary threat.

Small businesses and several states sued, arguing that a president cannot use emergency powers to impose what amount to taxes, a power the Constitution reserves for Congress. Even conservative justices voiced serious doubts during the hearing, questioning why allies such as Spain and France needed tariffs for national security reasons, and warning against handing presidents unlimited authority to tariff any product from any country at any time.

Roughly 90 billion dollars in tariffs already paid hangs in the balance, roughly half the tariff revenue collected in 2025 through September. A loss for the administration could mean refunds for businesses, though one justice cautioned the process could become a complete mess. A win would hand presidents a precedent for imposing tariffs whenever they choose, without congressional approval. A ruling is expected by June 2026.

Elsewhere in e-commerce, Walmart Marketplace has opened a seller forum, Amazon has added inventory placement fields with record delivery speeds, and Amazon expects a 5 percent jump in shipment volume this holiday season. A free dashboard tool for Amazon sellers has also been released that breaks down sales by state, city, zip code and hour, filterable by ASIN, SKU, business orders and Subscribe and Save orders, requiring only a single report upload from Seller Central.