How could this app possibly be considered a business associate to a provider? The provider has no idea it’s even being used, let alone a formal association with the application.

"Kate's App is a tool created to support medical caregivers"

The landing page doesn't make it clear whether providers are expected to use it or not.

Look up the definition of “provider” in HIPAA’s text. The definition is extremely broad and doesn’t just cover doctors and pharmacists.