[sushicat]

If we don’t talk about zero day vulnerability, which may be used by government to spy citizens, iMessage is end to end encrypted and secure.

Chinese local chat app like WeChat, or customized Android from Xiaomi or Huawei, they have back doors, which allow Chinese gov access data directly.

Spyware from unintentional vulnerability vs. intentional back doors are different.

[_-___________-_]

If your phone is backed up to iCloud, and your phone (or iCloud account, it's not clear) has the region set to China, then your messages are most likely accessible by the Chinese government, because Apple's cloud services are operated by a Chinese company in China, and Chinese companies don't have the option of resisting information requests from the government.