Walmart over the years has been working to turn its physical retail stores into online fulfillment centers, and now, with its latest set of test stores announced today, the retailer will try out ideas to make that transition more seamless. Walmart says it will deploy personnel to four test stores across the U.S., where they’ll prototype and iterate on new technology and tools that will serve the needs of Walmart’s in-store shoppers and online shoppers alike, including changes involving augmented reality, handheld mobile devices, new apps, in-store signage, omni-assortment, and revamped checkout stations. The idea is to turn these four test locations into rapid prototyping environments, where teams can test solutions in real-time, make changes, scale what works and scrap what doesn’t.