Rui + Sunday Lab

About     Contact                              

Sorta APP Design


END TO END APPLICATION UI/UX DESIGN



PROJECT OVERVIEW This is a real ongoing startup project. The actual design process was often non-linear and iterative, so I have extracted the key milestones and insights to present here. Our application aims to solve the waste sorting and retention problem for users in Luxembourg, helping the government meet the EU's 2030 sustainability standards.

MY ROLECo-founder, UI/UX Designer, Brand Designer
TOOLS Figma, Adobe CC, FigJam

MY DESIGN PROCESSResearch → Define → Ideate → Prototype →Test →↺

SUMMARYChallenge
  • Luxembourg's unified waste system still leaves residents confused with complex items and multi-material products
  • Collection schedules vary across 102 municipalities, complicating compliance
  • High expat population brings conflicting sorting habits from their home countries
  • Rising error rates hinder progress toward the EU's 2030 target of 60% recycling

Solution
  • Smart app providing localized, step-by-step sorting guidance
  • Barcode scanning and intelligent search to identify products and break down materials
  • Real-time municipal collection schedules and recycling center information
  • Future AI visual recognition and expansion into an educational eco-platform

Key Results
  • 90% task completion rate for core features, demonstrating seamless UX
  • Configuration-based architecture supporting all 102 Luxembourg municipalities
  • WCAG 2.1 AA compliant, ensuring equal access for all users
  • Crowd-sourced product database enabling continuous knowledge sharing and expansion




The current Android version, v0.0.51 (Build 122), is now available for download on Google Play. The iOS version is currently in the Apple Store submission process. Meanwhile, an updated version of the application is under active development.

RESEARCH COMPETITIVE & MARKET ANALYSIS

Market Context & Opportunity (Minimalist Version) Luxembourg's waste management landscape is characterized by three major pain points, creating a significant market gap:

I. Financial & Volume Crisis

  • The Problem: Highest per capita waste in Europe (721 kg/yr).
  • The Incentive: Correct sorting saves families up to €380 annually.
  • The Value: Convert compliance into strong financial motivation.

II. Cultural & Rules Gap

  • The Problem: 47% foreign residents struggle with 102 distinct municipal rules.
  • The Confusion: Knowledge gap due to differing international sorting norms.
  • The Value: Bridge the multilingual/regulatory gap with standardized guidance.

III. Regulatory & Compliance Gap

  • The Problem: Current 50% recycling rate falls short of the EU's 60% mandate (2030).
  • The Need: Marginal gains demand precise, household-level digital intervention.
  • The Value: Become the essential tool for achieving national compliance.

Market OpportunityThe convergence of these factors creates a €50 million European market opportunity (validated by successful B2G models like Italy's Junker). Luxembourg is identified as a high-value, underserved niche market:

  • Core Market: 680,000 Luxembourg residents, including 320,000 foreign residents (2024 STATEC), require multilingual, standardized guidance.
  • Secondary Market: 160,000 households (2021 STATEC) actively seeking cost-reduction strategies.
  • B2B Market: 3,000+ establishments in the HORECA sector (Hotels, Restaurants, Cafés) and tens of thousands of corporate offices (2024 STATEC) require compliant waste solutions.
 Ultra-Concise Strategic Advantage

I. Phase 1: Household Penetration (The Foundation)

  • Focus: Deliver product-level, multilingual guidance.
  • Goal: Precisely resolve core sorting errors for all residents.
  • Value: Establish a robust user base and data foundation.

II. Phase 2: B2B Market Expansion (The Profit)

  • Focus: Extend reach to the commercial sector (B2B).
  • Action: Integrate sophisticated compliance and reporting features.
  • Value: Leverage household credibility to secure B2B adoption and monetization.


Competitive Analysis & Strategic PivoOur preliminary competitive analysis was primarily centered on mapping competitor product categories and features.




Feedback-Driven Refinement Following early user interviews, it became clear that user retention poses the single greatest challenge in this sector, even for solutions endorsed by governmental bodies.

Therefore, I conducted a new, more comprehensive market study. The objective was to gather as much current data as possible on these applications, including their operational status, Monthly Active Users (MAU), and retention rates, to analyze the market reception and effectiveness of their user retention strategies. (Table Snippet Below):


Key Insights & Data Validation Snippet
1. User Retention Rate Assumptions (D30)
  • Industry Retention Benchmark: The average D30 retention rate across the industry remains low, typically ranging from 3% to 5% (validated by RecycleCoach research data).

2. User Base Sizing Methodology
  • Download-to-Active Conversion: Monthly Active Users (MAU) generally only account for 10% to 30% of the application's total download count.

3. Business Model Validation
  • B2G Dominance: The most successful applications in this sector are predominantly profitable through the B2G (Business-to-Government) model, charging municipalities for their services.

User Interview Methodology (Simplified)
1. Interview Objective
Objective: To compare two user groups (New Immigrants vs. Established Residents) to see if differences exist in waste sorting preferences, trust levels, and pain points.

2. Interview Guides
I drafted two interview guides, tailored for:
  1. New Immigrants/Expats (Residency < 6–12 months).
  2. Established Local Residents (Residency 12+ months).

3. Interview Strategy
Interviews are not simple Q&A sessions. We use the project goals as a foundation, leveraging Follow-up probes to constantly dig deeper, aiming to uncover latent needs that users may not even be aware of.

4. Interview Sample
For rapid iteration and efficient qualitative analysis, we used a small sample:

Total Participants: 5
  • 3 New Immigrants
  • 2 Local Residents



DEFINE
 Following 5 in-depth interviews (3 new immigrants, 2 local residents), I analyzed the data to identify recurring patterns and behavioral differences between user segments.Each key finding below was validated through multiple participant mentions, cross-referenced with competitive research data (retention rates, business models) and Luxembourg market statistics.

KEY FINDINGS EXCERPT
  1. Core Pain Points: Users Struggle Against a Complex and Imperfect System
  2. User Behavior: They Have Developed Their Own "Survival Strategies"
  3. Psychological Drivers: Environmental Concern is the Only Reliable, Yet Fragile, Internal Motive
  4. Product Value: Success Hinges on "Indispensable Dual Core" and a "Non-Negotiable Baseline"
  5. User Experience & Retention: Hinges on Utmost Simplicity and Optional Incentives
  6. Market Success: Hinges on Official Endorsement and Trust

Use These Key Findings
  1. Internal Alignment: Share with product, design, and development teams to ensure a unified understanding of the user.
  2. Guide the Roadmap: Use these findings to prioritize features (e.g., prioritize database completeness over gamification).
  3. Inform Design Principles:
    • "Design for an imperfect system."
    • "Integrate with existing behaviors, don't fight them."
    • "Prioritize convenience over education."
    • "Maximize simplicity, avoid bloat."
Based on distinct behavioral patterns from research, I developed two personas representing our primary user segments. These personas directly informed design decisions:  
  • Anna's need for instant answers → Scan feature priority  
  • Luc's need for official authority → Government data emphasis  
  • Both require simplicity → Minimalist 3-feature MVP


User Personas
With insights gathered from the research, I developed two primary personas representing new migrants to Luxembourg and long-term local residents. These personas have been instrumental in understanding the distinct needs, behavioral patterns, and pain points of users when navigating waste sorting in Luxembourg.

Persona 1: The New Migrant



Persona 2: The Local Resident



Our MVP is a direct response to the core user need for Efficiency and Simplicity.

The current prototype utilizes open-source data to rapidly validate the UX and technical feasibility of our core features (Scan, Calendar, Map). This strategic approach achieves two goals:
  1. Fast Validation: We test the product with users now, addressing immediate pain points like Anna Müller's.
  2. Strategic Leverage: The finished prototype serves as a powerful proof-of-concept for the Luxembourgish Government, significantly strengthening our partnership proposal to eventually satisfy the "Authority" and "Trust" needs of residents like Luc Hoffmann.


 Value Proposition：
Sorta transforms waste sorting from a multi-lingual chore into an efficient, trustworthy habit. Using our instant Scan to Sort technology, we provide definitive, municipally-validated answers, helping you save time, avoid fines, and comply with your community's standards.


IDEATE USER JOURNEY FLOWS




I partnered with the Business System Analyst to quickly produce comprehensive User Journey Flows, identifying critical Pain Points and Opportunities. The MVP focuses on Scan, Calendar, and Map. To illustrate the core interaction, a segment of the Scan Task Flow is presented below.



While I focused on the branding aspect, my colleague, the Business System Analyst, quickly drafted the low-fidelity wireframes based on our discussed framework and structure, allowing me to proceed to the next step.





BRANDINLOGO DESIGNInspired by the concept of planetary protection through scanning technology, my design creates an immersive spatial experience that invites exploration.

Primary Color Selection
After evaluating both blue and green options, the team selected a refreshing shade of green as our primary color. For optimal contrast, we developed darker tonal variations for use on light backgrounds.


To enhance intuitive material recognition, I developed a comprehensive illustration system that:


      Based on user interviews and competitive analysis, we needed a visual direction that offered warmth and engagement rather than cold compliance.

      I designed a Space-themed concept where recyclable materials are unique cosmic elements. This metaphor reframes sorting as an inspiring, fun contribution to the 'Sorta Universe,' transforming a mandatory chore into a globally significant action.


      UI Library Components



      PROTOTYPEHIGH-FIDELITY WIREFRAMES


      Leveraging the initial structure established in the low-fidelity model and the existing basic prototype, I swiftly transitioned to designing the final high-fidelity wireframes.





        Selected Proposals

             

        The container with its recycling category forms a card. Combined with the material composition, it creates a complete module showing:
        • The product structureCorresponding materialsAppropriate recycling container
        • Different item structures are displayed separately.
        • Users can click the dropdown arrow to view detailed category descriptions.



        Scan Results Display Optimization
        Tested multiple card layouts before finalizing:
        • Uses high-contrast color coding for containers
        • Segregates recyclable/non-recyclable items



        Selected Proposals
        Single-component items and  Multi-component items

               

        Material Efficiency Solution
        During testing with a live database, we discovered that:
        • Many items share identical materials across components
        • Original design caused repetitive icon displays



        Implemented Solution:
        • Consolidated identical materials under single icon
        • Supplemental text listing for duplicate parts
        • Maintains clarity while reducing visual clutter  

         

        Calendar Page Design
        Proposals


        Proposed container icon designs for daily recyclables display


        Selected Proposals
        • Color-coded recyclable dates using container-specific palette
        • Current date emphasized with enlarged circular highlight
        • Black container outlines for maximum contrast
        • Unique sustainability slogans per material type

        During testing with a live database, we discovered that:
        • We discovered through community waste data that many locations require simultaneous display of three different recycling containers. As a solution, I developed a three-panel daily display format.
               
        • Certain communities have unique recyclable materials, so I designed specialized container icons to ensure comprehensive coverage of all categories.





        Map Page Design
        For the Map page, I conducted thorough pin design testing and ultimately selected the most visually clear option. Users can click any location pin to view:
        • Recycling center details
        • Specific corner information




        Selected Proposals


        Accessibility Improvements (WCAG 2.1 Compliance) Tab Bar Optimization

        Following accessibility testing with Figma plugins, contrast issues were identified primarily in the tab bar text. To address this:
        • Unselected tab text was changed from gray to black to meet WCAG AA contrast requirements
        • Selected tab labels now display in bold weight for enhanced differentiation
        • Testing across color blindness modes (Protanopia, Deuteranopia, Tritanopia, and Achromatopsia) confirmed that users can clearly distinguish between selected and unselected states
        • Community section text was updated to black for improved readability

        Waste Category Visual Design


        Based on usability testing and accessibility validation:
        • Special waste categories were updated from the light primary green to a darker shade with enhanced contrast
        • Border weight was increased from 2px to 4px for better visibility
        • Color blindness testing verified that users can differentiate between various waste container types across all modes
        • Date selection now includes both iconography and text labels for clarity
        • Special selection indicators and current date markers remain visually distinct from one another
        TEST USABILITY TESTING METHODOLOGY We conducted primarily usability testing on version 0.0.52 with five initial participants.

        This iterative strategy (test, iterate, re-test) yields greater value than a single large study. We used qualitative data (exploring the 'why' and 'how') to inform our decisions, supported by quantitative metrics (assessing the 'how many' and 'how fast'), such as task completion time and success rates.

        We used the quantitative data to identify what occurred, and the qualitative data to determine the reason. Crucially, due to the small sample size, quantitative results are indicative, not statistically significant.


         SORTA App Usability Testing Report - Key Excerpts

        Executive SummaryTest Date: November 2025
        Participants: 5 users (3 New Immigrants, 2 Local Residents)
        Test Duration: 10-20 minutes per session
        Overall Success Rate: 68%
        Participant Breakdown
        • New Immigrants (<2 years): 3 participants (P1, P2, P5)
        • Local Residents (>5 years): 2 participants (P3, P4)
        • Platform Split: 3 iOS, 2 Android

         Critical Findings
        🔴 P1 Issues (Must Fix Immediately):
        • Language barrier severely impacts new immigrants (3/3 struggled with terminology)
        • Calendar "City" label confusing, especially for non-locals (4/5 participants)
        • Map feature purpose completely unclear (5/5 participants confused)
        • Commune selection not intuitive for newcomers (3/3 new immigrants struggled)

        🟡 P2 Issues (Should Fix Soon):
        • Carbon tracking has low appeal to both segments (4/5 not motivated)
        • Notification value proposition unclear (4/5 hesitated to enable)
        • New immigrants need more contextual help (3/3 wanted explanations)
        • Database gaps create immediate trust issues (2/3 new immigrants hit this)

        🟢 Positive Findings:
        • Scanning feature is universally valuable (5/5 completed successfully)
        • New immigrants HIGHLY motivated to use app (3/3 would use daily initially)
        • Calendar has strong appeal once understood (4/5 see long-term value)
        • App fills critical gap for newcomers (3/3 said "finally something useful!")
        Methodology Participants Profile


        Key Demographic Insights:
        • New immigrants represent 60% of test group (mirrors target market)
        • All 3 new immigrants are high-value users (high motivation, frequent use potential)
        • Local residents are skeptical users (know rules, see limited value)
        • Language diversity: 7 different languages across 5 participants

        Selected Design Iterations  
        • Scan Pop-Up & Editability
        The Scan modal now keeps the navigation bar persistently visible. The 'Add More Packaging' function uses an Edit Icon to clearly signal editability. For items lacking data, we display a default packaging type to maintain continuity with the manual edit mode.



        • Map Functionality
        The Map's default zoom range is widened to immediately show both Recycling Centres and local Drop-off Points. More actionable information has been added to the Map to aid user decision-making.


        Calendar Interface
        The Calendar layout was adjusted to eliminate confusion: Primary Brand Color is now used for an inner stroke to mark special collections (replacing grey), visually reinforcing the card design. Selected dates are highlighted by a black outer circle, defaulting to the current day. Short explanations for special collections are included.


        Selected Motion Highlights

        Future Impact 
        This MVP establishes the foundational solution for compliant recycling. Our roadmap is strategically focused on expanding utility and ensuring long-term retention:

        Key Future Initiatives

        1. AI Recognition: Training our model for photo-only object recognition, moving beyond barcode scanning for greater user efficiency.
        2. User Retention: Developing a robust community and rewards system to drive loyalty and foster a positive recycling culture.
        3. Sustainability Promotion: Integrating suggestions for recyclable alternatives and promoting local sustainable brands.
        4. Continuous Design Iteration: The design will be continuously refined based on user feedback and data.

        We aim to solidify Sorta as the trusted standard for waste management compliance in Luxembourg.

        Please feel free to reach out with any ideas, insights, or collaboration opportunities.

        ← Prev    Index    Next →


        ©Rui + Sunday Lab Luxembourg, LU.
        Creative Mind Exploring Digital Landscapes.