JUUIN
Shipped
Launching an End-to-End Corkage Reservation App to Enhance Dining Experiences for over 5,000 users in South Korea
Overview
When I joined JUUIN as a product designer, the team was in the early stages of defining both the product and the experience. After multiple pivots, our goal was to create a mobile app that would let users in South Korea purchase alcohol and reserve corkage-friendly restaurants in a single, seamless flow.
With no existing screens or systems in place, I was responsible for leading the overall experience design from concept to launch while iterating alongside engineers and stakeholders in a fast-paced startup environment.
The JUUIN iOS app successfully launched in Q2 of 2023.
Role
Founding Product Designer
in a cross-functional startup with
3 Founders and 2 Developers
Platform
Mobile App, iOS
Year
2021-2024
Impact
3,000+
beta test users through 3 phases of shipping
200+
restaurant partnerships acquired
60%
increase in restaurant corkage reservations
25%
increase in in-app order conversion rate
Context
Going from concept to launch
JUUIN is a mobile app that reimagines the corkage experience in South Korea by allowing users to purchase alcohol and reserve corkage-friendly restaurants in one seamless flow.
Driven by rising prices, changing drinking culture, and a growing appreciation for craft spirits, many users in South Korea began bringing their own bottles to restaurants. However, despite the growing demand, the corkage experience remained outdated: unclear, inconsistent, and inconvenient for both diners and restaurants.
Our team recognized an opportunity to turn this growing trend into a more intuitive and intentional dining experience. But as a startup, we faced significant challenges: no existing product infrastructure, a time-sensitive launch roadmap, and a business model that relied on balancing two equally critical components, alcohol and reservations.
Objective
Designing a seamless offline to online corkage experience
To succeed, we needed to validate user demand, define the core experience, and design a fully integrated solution that worked for both diners and restaurants—laying the groundwork for a scalable, service-driven marketplace.
As a founding product designer, I initially narrowed my focus to 4 critical design priorities to shape the product:
Designing a unified, linear reservation experience
The corkage flow had to guide users from alcohol to restaurant without backtracking or uncertainty.
Supporting both pathways:
Bring Your Own vs. In-app Purchase
While engineering constraints limited some ideal flows, the design needed to support both use cases without compromising usability.
Building confidence and clarity into every step
Key details like corkage fees, restaurant policies, and delivery timing had to be surfaced early and clearly. No buried fine print or last-minute surprises.
Minimizing drop-off through thoughtful defaults and streamlined input
Every extra step risked abandonment. I worked to reduce clicks, pre-fill selections, and only surface what was necessary at each point in the flow.
Constraints
Establishing boundaries and requirements
Given the unique business model and startup environment, the team identified and aligned key constraints to guide decisions and maintain clarity throughout the project:
Finding the right balance between alcohol and reservations
JUUIN was not just a reservation app or an alcohol delivery app, as the business model required it to be both. The corkage experience only worked when the two were seamlessly cocnnected. This mean we couldn't prioritize one over the other and both sides had to be considered equally to design a truly end-to-end experience.
Limited access to user data and research resources
As an early-stage startup, we had neither the budget nor the infrastructure to run formal research studies. I relied on user interviews, trend & market research, and corkage experience stories from blogs and social media to surface early insights and opportunity areas.
Building from zero
With no existing product to iterate on, I had to define everything from scratch including flows, features, content structure, and system. This required close coordination between design, engineering, operations, and stakeholders to align on foundational decisions quickly while staying flexible as business needs evolved.
Discover
Understanding the evolving drinking experience
To understand how people were actually drinking in South Korea and why there were choosing to corkage, I conducted user interviews with wine and spirits enthusiasts and ran desk research, reviewing customer trend reports and online discussions across blogs and social media. I aimed to understand not just behaviors, but also the cultural and emotional context behind shifting behaviors.
Research revealed a key user insight:
For many younger consumers, alcohol was becoming an intentional part of a larger, meaningful experience, whether for a celebration, a date, or a casual night out. They were drinking less but with more purpose: seeking thoughtful pairings, rare finds, and meaningful moments with people they loved.
However, the corkage process was harder than it needed to be and the pain points were clear for both restaurants and diners:
Limited alcohol options when dining out
Unclear and inconsistent policies
Having to carry heavy bottles on foot or public transport
Scattered information online
For Diners
No standard way to offer corkage
Corkage process handled manually, case-by-case
Disrupted service flow
Limited variety of alcohol due to lack of storage
For Restaurants
Define
Unpacking the real corkage problem
People wanted more control over their dining experiences, using corkage as a way to pair their preferred drinks with their meals. Yet, it wasn't working and this revealed a core opportunity.
How might we design a seamless corkage experience that gives users the freedom to drink what they want, where they want, without the usual friction?
Develop
Building the experience around flexibility
As I moved into prototyping, I focused on allowing users to choose without complexity and explore corkage in a way that matched their preferences, while keeping the experience simple and intuitive.
I focused on two key areas:
Reservation flow:
Support both JUUIN alcohol purchasers and BYOB users, ensuring the core experience works regardless of entry point
Scalable content architecture:
Organize 3,000 drinks and restaurants into clear, navigable categories to help users quickly understand options and make informed decisions
Validate
Reevaluating our assumptions
When we first launched, the message was simple. "Drink In Your Way." The goals was to give users full freedom over their dining and drinking experience through a easier corkage reservation system. However, we learned something unexpected through our testers:
Over 70% of beta users reported having limited knowledge of various alcohol and wanted more guidance
Most people were not wine or spirit experts. They were curious, open to trying new things, but unsure where to begin. This shifted our perspective.
If understanding a drink enhances the experience, then helping users discover their preferences has to be part of the product.
Iterate
Sharpening the product
With over 3,000 drinks and restaurants to choose from, full freedom also meant that it could be overwhelming. Users needed structure, but still without constraints. We moved away from "choose any combination" and focused on supporting exploration.
Social Proof Indicactor
Designing every entry point to be connected
Solution
An end-to-end corkage reservation app that makes BYOB effortless
Due to tight engineering constraints and shifting stakeholder priorities, not all of my designs were fully implemented in the final MVP. Some screens shipped with reduced functionality, while others remained as designed concepts for future iterations.
The following screens are walkthroughs of the intended user experience, designed to prioritize clarity, flexibility, and reduce friction at key moments of booking a corkage experience.
Screen 1: Corkage Reservation
Screen 2: Categorization
Screen 3: Restaurant Detail Page
Screen 4: Alcohol Detail Page
Takeaways
Designing through constant change
Working in a constantly changing startup environment pushed me to let go of rigid plans. I had to make fast decisions with incomplete information and stay open to being wrong. That mindset shift made me a better designer and teammate.
Prioritizing clarity over perfection
I used to feel pressure to get everything “right” the first time. But through this experience, I learned that momentum often matters more. Prioritizing clarity and usefulness, even if it meant imperfect execution, helped us move forward.
Collaborating across functions
As the only designer, I had to learn how to translate ideas across engineering, product, and operations. That meant asking better questions, explaining design choices simply, and knowing when to advocate or when to adapt.