Apple provides great security mechanisms like Keychain, data encryption, or App Transport Security(which forces developers to use SSL pinning). Keychain is the password management system developed by Apple. Logins, keys, and passwords should be stored in Keychain. For network request, SSL pinning is used to ensure that an application communicates with the right server. For this, we need to save the SSL certificate within the app bundle. Others security mechanisms are like using encryption methods like  AES-256 encryption while saving sensitive data to persistent storage or passing data over the internet.