China said Monday it would retire an app used to track COVID -19 contacts, a milestone in the country’s rapid turn away from its zero-tolerance coronavirus strategy. The state-run “Communications Itinerary Card”, which tracks whether someone has been to a high-risk area based on their phone signal, will go offline at 12 am Tuesday, according to an official WeChat post, after more than two years in operation. The “Itinerary Card” was a central part of China’s zero-COVID policy, with millions of people required to key in their phone numbers to produce its signature green arrow in order to travel between...