Barber-booking app adding 20L water bottle delivery: same app or a separate app?

You are the product manager for a consumer app that people use to book a barber. The business now wants this same app to solve another problem as well: letting customers order 20-liter bottles of drinking water. Should water ordering be built as a new feature inside the existing barber app, or launched as a separate app? Explain how you would reach the decision, and give your recommendation. ```hint Line the services up Compare the two services side by side: how often a customer needs each one, who the customer is, how an order gets fulfilled, and what a failed order costs. Then ask what each option lets the business reuse and what it forces it to build from scratch. ``` ### Clarifying Questions - Does the barber come to the customer's home, or does the app book a chair at a shop? And who would supply and deliver the water: our own staff, local vendors or a delivery partner? - What is the business trying to achieve with water ordering: more revenue per customer, more frequent app use, a new customer segment, or a first step toward a broader home-services platform? - How established is the barber app today (size of the customer base, retention, brand strength), and in which markets does it operate? - Would the people ordering water mostly be the same households that book barbers, or a different group such as offices and small shops? ### What a Strong Answer Covers - A goal-first framing: what the business wants from the new service, and which option serves that goal better. - A comparison of the two use cases on frequency, urgency, customer segment, fulfillment model and supply operations, and what that implies about user overlap. - The real costs and benefits of each path: shared accounts, payments and distribution versus a cluttered experience and brand dilution in one app; the expense of acquiring users from zero for a new app. - A clear recommendation, the evidence that would change it, and a low-cost way to test demand before committing. - Success metrics and guardrails for the chosen path, including protection of the core barber business. ### Follow-up Questions - A pilot inside the existing app shows that most water orders come from people who have never booked a barber. What does that tell you, and what would you do next? - Late water deliveries start producing one-star reviews of the app. How would you protect the barber business? - If the company later plans to add many more home services, does your answer change?