Fourth quarter gross margin increased to 23.0% from 19.8% quarter-over-quarter. Full-year gross margin improved to 22.8% from 22.6% year-over-year. GUANGZHOU, China, March 27, 2023 /PRNewswire/ — Viomi Technology Co., Ltd (“Viomi” or the “Company”) (NASDAQ: VIOT), a leading IoT @ Home…