Tencent, one of Asia’s biggest companies, is little known beyond the tech world. But its WeChat super app has more than a billion users worldwide. What started in 1998 when a small group of friends cloned an Israeli instant messaging service and adapted it for the Chinese market has become part of the fabric of life for people who use it to chat, shop, watch videos, play games, flirt, order food and taxis, and more. Now it’s attracted the attention of US President Donald Trump — and not in a good way.