Issuance
Apple uses Pass Type IDs and signing certificates. Google uses issuer accounts, classes, objects and service credentials. Onboarding must treat each relationship separately.
Updates and messaging
Apple ties a change message to a real pass change and it should not be used for non-critical marketing. Google offers modules and certain notifications with limits and anti-abuse controls.
Analytics
Neither provider turns every delivery or view into a perfect metric. Measurement combines observable states, owned clicks and business conversions.
Practical decision
When an audience mixes iPhone and Android, the question is usually not which one to choose but which common experience to preserve and which capabilities to adapt.