You are the PM of a Startup that launched a product to match people to play music together (similar to Tinder), how would you measure success of this product?

This question is asking you to step into the shoes of a Product Manager for a Startup, where the product is an app that matches people to play music together, and think about how you would measure the success of this product. Essentially, the interviewer is looking for you to demonstrate your understanding of various metrics that come into play when tracking the effectiveness and success of a product. They are asking for your understanding of product performance indicators, user engagement understanding, and long-term success parameters. The key points to focus on when answering this question are:

1. User acquisition: talk about how you will track user growth, new user acquisition or how many downloads the app has had.
2. User engagement: mention metrics like daily active users (DAUs), monthly active users (MAUs), session length, retention rate, etc.
3. Business metrics: discuss revenue, if the app is generating profit, or other financial indicators.
4. User Satisfaction: consider measures like review scores, feedback, Net Promoter Score (NPS).

Keep in mind to align these points with the goals of the product.

To gauge the success of a product like ours, we need to consider several key indicators. Firstly, we need to assess user acquisition, measured by the number of new users or subscribers, app downloads, or how many times our app appears in searches. Secondly, we should look at user engagement. This can be quantified through metrics like daily or monthly active users, the average session length, and the in-app interaction rate. Furthermore, retention rate or churn rate can provide insights into the app’s repeat usage.

We can't only rely on these user-focused metrics though. Financial metrics are equally important. We need to confirm if our business model is profitable by looking at our revenue growth rate, customer acquisition cost, and customer lifetime value.

Finally, user satisfaction measures like feedback, reviews, and our Net Promoter Score (NPS) will help us understand our users' experiences and levels of satisfaction. These measures together would provide a holistic insight into the success of our product.

A comprehensive evaluation of our product's success will feature a combination of several metrics.

For user acquisition measures, we'll track the number of app downloads, users registered, and the rate of growth over time.

We should also focus on user engagement metrics, like the average session length, active usage like the frequency of interactions within the app, number of matches made, and the percentage of users who return to the app after their first day (retention rate).

Importantly, we should also gauge financial success by looking at revenue (if a monetization strategy is in place), the customer acquisition cost, and how our operating cost relates to our revenues.

Lastly, it's crucial we understand our users’ satisfaction with our product through their reviews and ratings, survey responses, and the Net Promoter Score. Together, these metrics should give us a robust view of our product's success.