How would you measure App Store launch success?

## Prompt You are a Data Scientist at an e-commerce platform (e.g., Shopify) launching a new **App Store** (a two-sided marketplace connecting **merchants** who install apps and **developers** who publish apps). ### Task Describe **how you would measure whether the App Store launch is successful**. Your answer should include: 1. **Success definition / goals**: what “success” means for the business and for key users. 2. **Metrics framework** with: - A **North Star** metric (or 1–2 primary metrics) - **Diagnostic** metrics (funnel + marketplace health) - **Guardrail** metrics (avoid harming core product) 3. **Segmentation**: which cohorts or segments you’d cut by (merchant size, app categories, geography, new vs existing, etc.). 4. **Measurement strategy**: - How you would establish a baseline and evaluate lift (A/B test vs quasi-experiment) - How you would handle common issues (seasonality, cannibalization, delayed impact, selection bias) 5. **What data you’d need** (key events/tables you would instrument or validate). ### Output expectation Provide a structured plan and explain tradeoffs. You may assume you can instrument events in the product and access transactional data.