Design the event instrumentation for Apple TV+ at scale at global scale

Problem Statement Description

Product context: Apple is a consumer hardware, software, and services company; its products include iPhone, iPad, Mac, Apple Watch, AirPods, iOS, App Store, iCloud, Apple Music, and Apple TV+.

Apple TV+ is consumed across a global ecosystem of Apple devices, smart TVs, web browsers, game consoles, and streaming devices. For this interview, you are asked to design the event instrumentation system that enables Apple TV+ product, engineering, analytics, operations, and business teams to understand user behavior and service health at scale without compromising Apple’s expectations for privacy, trust, and premium user experience.

Focus on the instrumentation layer for core Apple TV+ workflows: onboarding, sign-in, subscription eligibility, browsing, search, playback start, playback quality, content engagement, device switching, downloads, family sharing, accessibility usage, and cancellation or renewal journeys. The system should support both Apple-native experiences and non-Apple device surfaces, with particular attention to users who move between devices or are new to the Apple ecosystem.

This is a technical product management problem, so your response should clarify requirements, event taxonomy, data contracts, client/server responsibilities, reliability expectations, privacy constraints, rollout approach, observability, and trade-offs. You are not expected to design a full analytics dashboard or prescribe business decisions, but you should define how trustworthy, useful, and scalable event data would be captured and made available.

The experience should consider:

- The key users of instrumentation data, including product teams, playback engineering, content operations, growth, finance, customer support, and privacy/compliance partners.

- Critical user journeys and where event capture is needed across devices, sessions, regions, account states, and subscription states.

- Event schema design, naming conventions, metadata, versioning, deduplication, sequencing, and backward compatibility.

- Client-side versus server-side instrumentation trade-offs for playback, entitlement, billing, recommendations, and cross-device continuity.

- Privacy by design, consent, data minimization, retention, regional regulation, child/family account considerations, and secure handling of identifiers.

- Reliability requirements such as offline buffering, retry behavior, sampling, latency, data quality monitoring, and resilience during peak launches.

- APIs, SDKs, data pipelines, observability, validation tooling, and incident response processes needed to operate instrumentation globally.

- Rollout strategy across platforms, including testing, phased deployment, developer adoption, migration from legacy events, and rollback criteria.

Your goal is to describe a technically sound instrumentation product that helps Apple TV+ make confident product and operational decisions while preserving user trust, supporting global scale, and maintaining a high-quality streaming experience across the broader Apple ecosystem and partner devices.