I think it is unclear. For example Apple has HealthKit which collects health related data.. That data is probably HIPAA protected. If it's not (and if Facebook is not) then I would imagine we will see legislation and/or lawsuits to clarify things.
"If an entity does not meet the definition of a covered entity or business associate, it does not have to comply with the HIPAA Rules."
[0] - https://www.hhs.gov/hipaa/for-professionals/covered-entities...