The mayor's announcement says the app will protect phones by detecting malware and warning users of its presence. It will then recommend steps users can take to protect themselves and their phones, such as disconnecting from a WiFi connection that it has detected as malicious, navigating away from a compromised website or uninstalling an app it says is loaded with malware.
In addition to releasing an app this summer, NYC is also boosting its public WiFi connections' security measures. This extra layer of security can apparently prevent people connected to it from downloading malicious software and from accessing phishing websites. According to the mayor's office, it also has the power to do its job without using or storing personally identifiable info, just like the NYC Secure app. The city has already rolled out that extra layer to 18 NYC agencies' private networks, and it intends to deploy it across all government agencies and public WiFi providers before the year ends.