WeChat is the most popular messaging app in China, and that's largely because many of the others are banned in the country - like Facebook Messenger and WhatsApp. And today, a government watchdog acknowledged that Chinese authorities are able to retrieve messages from WeChat, even those that were supposedly deleted. Now this isn't much of a surprise, as many believed that the Chinese government was able to retrieve messages from WeChat, but it does confirm it.
Tencent is the parent company behind WeChat, and it has stated in a social media post that "WeChat does not store any chat histories - they are only stores on users' phones and computers." Essentially denying that it has done anything wrong. Now while Tencent may not store chat histories, that doesn't mean that the Chinese government isn't able to access them. There is likely a backdoor in WeChat to access these messages, which authorities say are only to help catch criminals and such. This isn't new, and isn't exclusive to China either. Many countries have access to deleted messages from messaging apps like WeChat, which is why it's important to remember that anything you post online is there forever, whether you have deleted it or not.
WeChat is a very popular app in China, in fact there is really no other alternative to WeChat in the country. It is essentially a messaging app mixed with Facebook and Twitter all in one service. There is a social media aspect to it, where you can post status updates, pictures and more for your friends to see. You can also make payments with WeChat, so it's basically a Swiss Army knife of Social Media. This confirmation will likely not result in less people using WeChat, just was the case with Facebook in the Western part of the world, when the Cambridge Analytica scandal took place. It's such a popular service, and one that people use all day, every day, that many just can't stop using it. This also might explain why Australia banned WeChat from Military grounds back in March. The fear that the Chinese could use it to discover where bases are and such.