Zalando, the big German-based internet retailer, reports a 35 percent sales increase to €501 million in the first quarter, including a rise of 27 percent to €223 million in the German-speaking area. The operating margin remained negative but improved to a loss equivalent to 6.5 percent of sales from 7.2 percent a year ago. The number of active customers went up to 13.5 million from 10.3 million. The number of visits increased to 332 million from 275 million and more than 38 percent of them were made with a tablet or a smartphone (more in Shoe Intelligence).