"Zippin, with $2.7 million in venture capital backing, has opened the first San Francisco competitor to Amazon’s cashier-less stores, whose three local locations have introduced SF customers to the concept of a business without a checkout register. Instead, sensors track what customers take, and software bills them electronically. Zippin’s technology, like that developed for Amazon Go, lets customers check into a store with a proprietary app, grab what they wish, then leave without being rung up at a register. Zippin’s cameras and a series of shelf weight sensors trace customers’ purchases and bill them accordingly." - Caleb Pershan