How to spy on someone’s Snapchat without them knowing?

Let’s make it clear: you cannot spy on someone’s Snapchat, except following activities visible to everyone on social media. However, you can spy on someone’s Snapchat messages by using a spy application. This kind of software runs in the background and remains undetectable after the installation. This allows spying on someone’s Snapchat chats without the target person knowing. The most famous apps that monitor Snapchat Direct are mSpy, FoneMonitor, Spymyfone, Flexispy.