WeChat is best known as China’s all-purpose “super-app”. It is used for everything from messaging and mobile payments to shopping and government services. As of June 2024, WeChat reported a staggering 1.37 billion active monthly users globally. For many Chinese-speaking diaspora communities – such as in the United States, Australia and the United Kingdom – the app is a lifeline to their homeland and communities.But my new research, published this week in Policy & Internet, shows WeChat has also become a powerful – and largely overlooked – component of China’s policing and public security infrastructure.In fact, the app is now functioning as a “police app”. It’s a kind a digital toolkit allowing police to collect intelligence, accept crime reports, verify identities and access citizen data through a private platform that is deeply embedded in everyday life. From a social platform to a policing toolPublic security bureaus in China began creating official WeChat accounts in 2012.By 2017, more than 50,000 police accounts existed. Many offered far more than simple announcements.Across provinces in China, police are now using WeChat to:operate “internet police stations” where citizens report crimes and disturbancescollect digital tips, images and clues from usersrun real-time emergency “WeChat alarms”verify identities using national ID datalink WeChat inputs to provincial “police clouds” and population surveillance databases.In some jurisdictions, WeChat has even become a frontline policing tool. In Guangzhou city, for example, railway police built a WeChat-based alarm system allowing citizens to send incident details directly to police dispatch. This would then trigger real-time audio and video communication. In Zhejiang province, officers used WeChat-based facial and ID card scanning to rapidly identify individuals.In several towns, thousands of “WeChat police groups” were created, pairing residents with local officers and blurring the line between neighbourhood governance and digital surveillance.These functions go far beyond convenience. They show how a commercial platform has become an extension of the state’s security apparatus.A patchwork of purposesMy research draws on 53 government procurement documents and additional Chinese-language media reports on two WeChat accounts known as “public security WeChat” and “WeChat policing”. Procurement documents are a great source of data. They are common in research in contexts where information is curated or suppressed.The research shows how police agencies across China are integrating WeChat directly into their daily operations. Wealthier provinces such as Fujian and Shanghai invested heavily in integrating WeChat with existing public security systems, enabling hundreds of services through the app. Fujian province alone aimed to link WeChat with services across ten cities and more than 300 functions.Other localities treated WeChat as a superficial PR tool. Some accounts offered little more than positive police stories or traffic announcements. Others became “zombie accounts” – created to meet digitisation targets but never properly maintained.This patchwork reflects broader challenges in China’s digital modernisation. Local agencies face unequal resources, tight performance quotas and limited technical capacity. For some, deep integration is possible. For others, the use of WeChat is merely symbolic compliance with government modernisation quotas.Filling a gap for the stateThe Chinese government has spent a decade pushing public security agencies to deliver more services online. Yet many local police units lack the expertise or funds to build bespoke digital systems. WeChat offers a shortcut.Because it already handles identity verification, payments, location data and messaging for more than a billion users, it can serve as a ready-made platform for police. Tencent, WeChat’s parent company, has positioned itself strategically. It offers customised WeChat modules to public security departments as a commercial serviceThe result is a public-private security infrastructure: state needs and corporate incentives moving in the same direction.Around the world, governments are increasingly partnering with private tech companies for policing and security. In the United States and Europe, for example, Palantir and similar firms provide predictive policing and data-analysis platforms.China’s version is different because WeChat is both a consumer platform and a part of the state’s digital infrastructure. When policing functions are embedded inside an app billions of people rely on for daily life, the boundary between public service and surveillance becomes blurred.A new future of platform power and state surveillanceFor citizens, WeChat-based policing can make bureaucratic processes faster and more convenient. But it also means everyday digital activities such as sending messages or paying bills and reporting disturbances could feed into a security architecture operated jointly by the state and a private company. For WeChat, being compliant with the demands of the state will likely be a crucial business survival strategy. For example, following China’s national crackdown on Tencent and the broader tech sector between 2020 and 2022, Tencent’s founder promised:Tencent will continue to resonate with the needs of the nation and the times.As China continues to centralise its digital governance, WeChat’s role in public security is likely to deepen – representing a new future of platform power and state surveillance.Ausma Bernot does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.