Steven SewellMobile Application Developer
GitHubLinkedIn

Cross-Platform Development · UI/UX Systems · Full-Stack Engineering · Independent Product Ownership & Delivery

Mobile Application Developer

Designing and launching polished cross-platform products.

End-to-end product development across web, PWA, Android, and Apple-platform workflows.

Explore selected work GitHub

01 / Selected products

Flagship products built end to end.

Selected work across mobile, data, commerce, and platforms.

01Sports Data · Personalized Product Platform

Pro Hockey Dashboard

A commercial-style multi-league hockey platform combining scores, schedules, standings, maps, player and roster research, authenticated personalization, Premium access, and subscription workflows.

Status
Production web and PWA product
Ownership
Independent end-to-end product ownership

Selected systems

  • Next.js 16
  • React 19
  • TypeScript
  • Tailwind CSS
  • Framer Motion
  • Mapbox GL JS
  • Supabase Auth
  • Supabase Postgres
  • Neon Postgres
  • Prisma
  • Stripe
  • Vercel
  • Netlify

End-to-end ownership

  • Product and interface design
  • Front-end engineering and full-stack integration
  • Sports-data architecture
  • Authentication, accounts, and Premium access
  • Deployment and product operations

Product considerations

  • Privacy, Terms, and account-deletion surfaces
  • Server-only secret separation
  • Licensing-conscious asset usage and removal of unauthorized logos and portraits
  • Subscription entitlement integrity
  • Mobile-distribution planning without claiming a released native application
View case study

02Health Information · Personal Tracking · Research

Nutrition & Supplementation Tracker

A nutrition and supplementation management application for organizing supplement routines, dosage and category details, tracking daily completion, maintaining authenticated personal records, and saving source-backed health and nutrition references in one structured workspace.

Status
Modernized full-stack application in active development
Ownership
Independent end-to-end product ownership

Selected systems

  • Next.js 16
  • React
  • TypeScript
  • Firebase Authentication
  • Cloud Firestore
  • Firebase Storage
  • Firebase Emulator Suite
  • Vitest

End-to-end ownership

  • Product and interface refinement
  • Front-end engineering
  • Firebase integration
  • Security-rule design and testing
  • External-source sanitization
  • Documentation and validation

Product considerations

  • Nutrition and health information is presented for general informational use rather than medical advice.
  • User records remain isolated through authenticated access controls.
  • External content is sanitized and source-attributed before presentation.
View case study

03Mobile · PWA · Sports Data

World Soccer Dashboard

A World Cup companion application featuring daily matches, venue maps, schedules, calendars, standings, teams, statistics, knockout visualization, detailed match pages, PWA support, and Android packaging.

Status
Version 1.0 web and Android baseline
Ownership
Independent end-to-end product ownership

Selected systems

  • Next.js 16
  • React 19
  • TypeScript
  • Tailwind CSS
  • Framer Motion
  • Mapbox GL JS
  • API-Football
  • PWA manifests and service worker
  • Capacitor
  • Android Studio
  • Vercel

End-to-end ownership

  • Product and interface design
  • Front-end and data-integration engineering
  • Calendar, map, and bracket visualization
  • PWA development
  • Android packaging and release preparation

Product considerations

  • Android target SDK requirements
  • Google Play release preparation without claiming completed review
  • Privacy policy and Data Safety documentation
  • Content rating and store listing assets
  • Source-backed data integrity
View case studyVisit live product

04Business Operations · Compliance · SaaS

EntityAtlasEntrepreneur Dashboard

A founder-focused business operations dashboard for organizing legal entities, formation workflows, state requirements, domains, documents, expenses, business profiles, and curated operational resources.

Status
Production-deployed SaaS platform in active development
Ownership
Independent end-to-end product ownership

Selected systems

  • Next.js 16 App Router
  • React 19
  • TypeScript
  • Tailwind CSS 4
  • Framer Motion
  • Supabase Auth
  • Supabase Postgres
  • Supabase SSR
  • Stripe Checkout
  • Stripe webhooks
  • react-qr-code
  • RDAP
  • Vercel
  • Netlify

End-to-end ownership

  • Product strategy and interface design
  • Full-stack integration and data modeling
  • Business-compliance workflows
  • Authentication and payments
  • Deployment

Product considerations

  • Clear legal-information disclaimers
  • Privacy, Terms, account, and password workflows
  • Server-only secret handling and business-information privacy
  • Guidance distinguished from legal advice
  • State, entity-type, subscription, and profile variability
View case studyVisit live product

05Financial Data · Customizable Dashboard

Investment & Assets Dashboard

A customizable market-data workspace combining stocks, cryptocurrency, commodities, currencies, indices, macroeconomic indicators, charts, earnings, news, and user-controlled dashboard layouts.

Status
Production-deployed market dashboard in active development
Ownership
Independent end-to-end product ownership

Selected systems

  • Next.js 16
  • React 19
  • TypeScript
  • Tailwind CSS 4
  • lightweight-charts
  • Recharts
  • React Grid Layout
  • Supabase Auth
  • Supabase cloud persistence
  • LocalStorage
  • Server API routes
  • Vercel
  • Netlify

End-to-end ownership

  • Product and interface design
  • Front-end engineering
  • Market-data integration and visualization
  • Authentication
  • Customizable workspace architecture

Product considerations

  • Delayed-data labeling and source transparency
  • Clear non-advisory positioning with no guaranteed accuracy or returns
  • Provider failure states
  • Secure environment variables
  • Privacy-aware authentication and user-specific layouts
View case studyVisit live product

06Inventory · Commerce Workflow · Image Analysis

CardVault

A trading-card inventory, collection management, and resale-preparation application combining card lookup, private cataloging, pricing context, condition assessment, grading estimates, photo analysis, listing preparation, exports, and creator-oriented rip sessions.

Status
Advanced commercial prototype
Ownership
Independent end-to-end product ownership

Selected systems

  • Next.js
  • React
  • TypeScript
  • Tailwind CSS
  • Supabase Auth
  • Supabase Postgres
  • Supabase Storage
  • Row-level security
  • FastAPI
  • OpenCV
  • External catalog adapters
  • GitHub Actions
  • LocalStorage fallback

End-to-end ownership

  • Product planning and workflow design
  • Front-end engineering
  • Database and repository architecture
  • External catalog, pricing, and listing integrations
  • Production-readiness planning, tests, and documentation

Product considerations

  • Private inventory and marketplace safeguards
  • Responsible grading and pricing language
  • Pricing, condition, grading, and AI analysis are advisory rather than guaranteed
  • Data export and user control
  • Automated tests and CI
View case study

02 / Additional work

Additional products.

Cybersecurity · Privacy · Browser Extension

Cybersecurity Browser Extension

An upcoming browser-extension project focused on privacy and cybersecurity workflows. Detailed scope and implementation evidence will be added after review.

Data Aggregation · Gaming Platform

Patch Notes

A console and live-service game update tracker combining official patch sources, normalized metadata, update history, source-confidence states, season scheduling, calendars, and source-health information.

  • Next.js
  • React
  • TypeScript
  • Tailwind CSS
  • Cheerio
  • FullCalendar
  • Serverless API routes
  • Caching and fallbacks
  • Vercel-compatible deployment architecture

Gaming Media · Creator Platform

Gaming Clips

A streaming-style gaming media product for highlights, full replays, live streams, screenshot albums, creator pages, channel collections, and publishing workflows.

Photography portfolio

Crowned One Photography

A photography portfolio presenting original photography and edited visual work through a responsive gallery experience.

Application Quality · Privacy · Launch Readiness

Application Pre-Launch Verification

A pre-launch application verification service that organizes architecture, code quality, exposed-secret risk, authentication, dependency health, licensing, privacy alignment, build integrity, deployment readiness, and marketplace requirements into one structured, severity-ranked review. Business-name and entity checks remain an optional secondary service.

  • Next.js 16
  • React 19
  • TypeScript
  • Tailwind CSS 4
  • Motion
  • Lucide React
  • Geist
  • ESLint
  • Prettier
  • Static typed content modules
  • Server Components by default

Local Discovery · Maps · Regional Guide

Raritan Bayshore Explorer

A map-first regional discovery guide for the Raritan Bayshore and nearby Monmouth–Middlesex coastal communities, combining curated destinations, local search, Map and List exploration, place and town pages, itineraries, transit context, and optional provider enrichment.

  • Next.js 15
  • React 19
  • TypeScript
  • Tailwind CSS 4
  • Mapbox GL JS
  • GTFS-derived transit data
  • Google Places API
  • Vitest
  • Playwright

03 / Technical and product expertise

Product design and full-stack delivery.

UI/UX leads a cross-platform practice spanning frontend, backend, data, security, deployment, and operations.

01

Product Design, UI/UX, and Interface Systems

A primary strength: turning complex requirements and information into polished, understandable, responsive user experiences.

  • UI and UX design
  • Information architecture
  • User flows
  • Mobile-first design
  • Responsive layouts
  • Data-dense dashboard and map UX
  • Interface systems
  • Design systems
  • Design tokens, theming, and dark-mode systems
  • Navigation and content hierarchy
  • Accessibility
  • Interaction states
  • Loading, empty, error, success, and gated states
  • Motion and transitions
  • Product copy
  • Cross-platform visual consistency
  • Interface QA and responsive refinement
  • Cross-browser refinement
  • Touch-oriented interfaces
02

Cross-Platform Application Development

Shared product architecture designed and tested for installable, touch-oriented experiences across web, mobile, and browser environments.

  • Responsive web applications
  • Progressive Web Apps
  • Capacitor
  • Android application packaging
  • Android Studio
  • Google Play release preparation
  • iPhone and iPad experiences
  • iOS and iPadOS interface considerations
  • Apple App Store preparation and distribution planning
  • Shared cross-platform architecture
  • Browser extensions
  • Mobile and desktop browser compatibility
  • Touch and installable experiences
03

Front-End and Interaction Engineering

Interface judgment translated into accessible component systems, data-rich workflows, and responsive product interactions.

  • Next.js
  • React
  • TypeScript
  • JavaScript
  • HTML
  • CSS
  • Tailwind CSS
  • Bootstrap
  • Framer Motion
  • Mapbox
  • Dashboards
  • Calendars
  • Maps
  • Data visualization
  • Responsive design
  • Browser compatibility
  • Component systems
  • Server and Client Component boundaries
04

Backend, APIs, and Data Systems

Practical product-level backend experience across application logic, provider integrations, identity, validation, and persistence.

  • Next.js route handlers
  • Server Actions
  • Node.js
  • Express
  • REST APIs
  • Provider adapters
  • Data normalization
  • Schema validation
  • PostgreSQL
  • Supabase
  • Neon
  • Prisma
  • Firebase
  • Authentication
  • Profiles and entitlements
  • Webhooks
  • Caching and fallback behavior
  • Migrations and indexes
  • Row-level security
  • LocalStorage
  • Import and export workflows
05

Security, Privacy, Authentication, and Compliance

Secure product-development practices, thoughtful authentication, privacy, permissions, and platform compliance.

  • Authentication and authorization
  • Secure session handling
  • Row-level security
  • Role and entitlement controls
  • Server-only secrets
  • Environment-variable management
  • Private storage
  • Signed media access
  • Database permissions
  • Dependency review
  • Secure API handling
  • Privacy policies
  • Account deletion
  • Data Safety documentation
  • Licensing awareness
  • App-store compliance
  • Subscription integrity
  • Responsible information handling
06

Product Operations, Business Systems, and Deployment

Independent product and project ownership connecting strategy, delivery planning, business workflows, release preparation, and production care.

  • Product ideation and strategy
  • Requirements definition
  • Roadmapping and feature prioritization
  • Scope and milestone planning
  • Project management
  • Backlog organization
  • Architecture planning
  • Documentation and QA
  • Issue triage
  • Release planning
  • Git and GitHub
  • GitHub Desktop and Actions
  • Vercel and Netlify
  • Cross-system product operations
  • Multi-environment and dual-host delivery
  • Environment, secrets, and authentication parity
  • Environment management
  • Build troubleshooting
  • Production validation
  • Domain and DNS workflows
  • Application packaging
  • Store-release preparation
  • Deployment and maintenance
  • Product iteration
  • Subscription products
  • Privacy and support documentation
  • Business-entity and compliance workflows
  • Salesforce
  • Commercial launch preparation

04 / Platforms and working environments

Platforms, tools, and delivery environments.

Experience across operating systems, devices, browsers, design tools, and deployment platforms.

Platforms and devices

  • Windows
  • macOS
  • Linux
  • Android
  • iOS
  • iPadOS
  • Responsive web
  • Progressive Web Apps
  • Desktop and mobile browsers
  • Phones, tablets, laptops, and desktops

Product and design tools

  • Figma
  • Adobe Creative Cloud
  • Adobe Express
  • Photography
  • Image editing
  • Interface mockups
  • Application icons
  • Product branding
  • Store graphics
  • Visual-asset preparation

Development environments and workflow

  • WebStorm
  • Visual Studio Code
  • Android Studio
  • Postman
  • Browser developer tools
  • GitHub Desktop
  • GitHub
  • Notion
  • npm
  • pnpm
  • Vitest
  • Playwright

Cloud, data, integrations, and delivery

  • Vercel
  • Netlify
  • Supabase
  • Neon
  • Firebase
  • Stripe
  • Mapbox
  • GitHub Actions
  • Capacitor
  • Google Play Console

Product domains

Domain breadth grounded in product delivery.

  • Business OperationsEntrepreneurship · Legal and compliance workflows · Application verification and launch compliance · General productivity tools
  • Sports and StatisticsSports · Statistics and analytics · Health and fitness
  • Financial DataFinancial and market data · Business decision support
  • Gaming and MediaGaming · Media and content organization · Photography and creative media
  • Collectibles and CommerceCollectibles · Commerce and resale
  • Privacy-Focused ProductsPrivacy-focused products · Personal and business information workflows

05 / Product delivery

From strategy to release.

A focused process spanning definition, UI/UX, architecture, engineering, validation, deployment, and iteration.

  1. 01

    Product strategy and roadmap

    Define the product opportunity, users, requirements, scope, feature priorities, roadmap, milestones, constraints, and standard for a useful release.

  2. 02

    UI/UX and architecture

    Design information architecture, user flows, responsive interface systems, application structure, data models, integration boundaries, and platform behavior together.

  3. 03

    Engineering and validation

    Engineer frontend and backend systems, connect APIs and data, implement authentication and product services, and validate behavior across devices, browsers, and target platforms.

  4. 04

    Release and continued ownership

    Complete QA, documentation, privacy and platform requirements, application packaging, deployment, release preparation, production troubleshooting, maintenance, and continued iteration.

06 / Education

Foundations in software development and health sciences.

01

Certificate in Full Stack Web Development

University of Texas Center for Professional Education

Full-stack application development and product engineering

02

Bachelor of Science in Health Sciences

University of South Florida

  • Public Health
  • Healthcare Administration