Hire the Best Windows App Developers
in the United States

25+ years in software, 17+ years in mobile, and 700+ apps delivered. I build and scale iOS, Android, Flutter & React Native products end to end - from architecture and backend integrations to launch, monetization, performance, and long-term growth. 👋 Hi! I’m a veteran full stack developer, mobile app developer, and team lead leading a senior long-term team capable of taking products from idea → launch → scale → maintenance. I’ve been in professional software development for 25+ years and mobile app development for 17+ years, delivering scalable iOS Development, Android App Development, Flutter, React Native, and backend-driven platforms across startups, SaaS products, enterprises, and high-growth mobile ecosystems. Clients usually come to us when they need more than just coding - they need a technical partner who understands architecture, business logic, scalability, monetization, and long-term product growth. 🏆 Why Clients Choose Me ✔️ 25+ years as a full stack developer and software architect
 ✔️ 17+ years in mobile app development
 ✔️ 700+ mobile apps delivered across iOS, Android, Flutter & React Native
 ✔️ Expertise in native app development, hybrid app development, and scalable backend systems
 ✔️ Reduced crash rates by up to 70% and improved app performance by 50% on production apps
 ✔️ Built mobile platforms used by 5M+ users worldwide
 ✔️ Strong experience with Mobile App Improvement, Mobile App Bug Fix, and modernization projects
 ✔️ Long-term experience with startups, SaaS companies, enterprises, and Fortune 500 clients
 ✔️ Full-cycle delivery: architecture → development → deployment → scaling → suppo As a mobile application developer, ios developer, android developer, flutter developer, and full stack developer, I specialize in building high-performance native and cross-platform mobile apps used by millions of users worldwide. I work with native iOS development using Swift, SwiftUI, UIKit, and Objective-C, native Android development with Kotlin and Java, as well as Flutter, React Native, and hybrid app development for scalable cross-platform delivery. Over the years, I’ve helped build 700+ apps across fintech, healthcare, social networking, education, entertainment, e-commerce, IoT, and enterprise SaaS. My experience covers the full mobile app development lifecycle - system architecture, UI/UX implementation, backend development, API Integration, DevOps, deployment, scaling, optimization, and long-term product evolution. 📱 Native iOS & Android Development • Native iOS Development with Swift, SwiftUI, UIKit, Combine, Objective-C • Native Android App Development with Kotlin, Java, Jetpack Compose • Smartphone app optimization for performance, UX, and scalability • Clean Architecture, MVVM, VIPER, modular app structures • Device integrations: BLE, GPS, biometrics, camera, sensors, HealthKit, Google Fit • App Store & Google Play deployment pipelines • Multi-language apps with localization and accessibility support • Advanced performance optimization and memory management 🔁 Cross-Platform & Hybrid App Development • Flutter developer expertise for scalable cross-platform products • React Native development with custom native module integrations • Kotlin Multiplatform Mobile (KMM/KMP) • Shared business logic across iOS and Android • Adaptive UI systems and responsive mobile layouts • Cross-platform architectures reducing development time by 40–60% 🔧 Backend, API Integration & Infrastructure • REST API and GraphQL API Integration • Firebase, Node.js, PHP, and scalable backend services • Authentication systems, caching, offline sync, token management • SQLite, Room, Realm, Core Data • Push notifications: FCM, APNS, OneSignal • Real-time chat, geolocation systems, dashboards, and live data platforms • Backend-connected mobile ecosystems with scalable cloud infrastructure ⚙️ DevOps, CI/CD & Delivery • Fastlane, GitHub Actions, Bitrise, Firebase App Distribution • Automated testing and deployment pipelines • Beta testing, crash analytics, staged rollouts • CI/CD optimization for faster and safer release cycles • AWS and scalable cloud deployment workflows 📊 Analytics & Monetization • Firebase Analytics, Mixpanel, Amplitude, Google Analytics • In-app purchases, subscriptions, AdMob, Facebook Ads • Retention optimization and funnel analytics • Data-driven product iteration and growth optimization 🔌 Advanced SDK & Hardware Integrations • AVFoundation, CameraX, Core Bluetooth, Core Motion • Stripe, Twilio, Agora, Sendbird, Mapbox, OpenCV • IoT dashboards, BLE integrations, voice/video systems • Camera-heavy and sensor-based mobile applications 🌍 Industries Served • Fintech & Banking • Healthcare & Fitness • E-commerce & Retail • Smart Home & IoT • Education & E-learning • Social Networking • Travel & Hospitality • Entertainment & Media • SaaS & Enterprise Platforms ✅ Let’s Build a Mobile Product That Scales!

✅ 𝗠𝘂𝗹𝘁𝗶𝗽𝗹𝗲 𝟳-𝟴 𝗳𝗶𝗴𝘂𝗿𝗲 𝘀𝘂𝗰𝗰𝗲𝘀𝘀𝗲𝘀 & 𝗦𝗮𝗮𝗦 𝗰𝗹𝗶𝗲𝗻𝘁𝘀/𝗮𝗽𝗽𝘀 𝗮𝗰𝗾𝘂𝗶𝗿𝗲𝗱. ✅ 𝟳𝟱+ 𝗮𝗽𝗽𝘀 𝗯𝘂𝗶𝗹𝘁. 𝟭𝟭+ 𝘆𝗲𝗮𝗿𝘀 𝗽𝗿𝗼𝗳𝗲𝘀𝘀𝗶𝗼𝗻𝗮𝗹 𝗲𝘅𝗽𝗲𝗿𝗶𝗲𝗻𝗰𝗲. ✅ 𝗔𝗰𝗰𝘂𝗿𝗮𝘁𝗲 & 𝗴𝘂𝗮𝗿𝗮𝗻𝘁𝗲𝗲𝗱 𝗾𝘂𝗼𝘁𝗲𝘀 𝘄𝗶𝘁𝗵 𝟯𝟬-𝟰𝟬% 𝗹𝗼𝘄𝗲𝗿 𝗰𝗼𝘀𝘁𝘀 𝗮𝗻𝗱 𝗱𝗲𝘃 𝘁𝗶𝗺𝗲𝘀 𝘁𝗵𝗿𝗼𝘂𝗴𝗵 𝗽𝗿𝗼𝗽𝗿𝗶𝗲𝘁𝗮𝗿𝘆 𝗳𝗿𝗮𝗺𝗲𝘄𝗼𝗿𝗸 𝘂𝘀𝗲(prebuilt-SaaS code). ✅ 𝗣𝗵𝗲𝗻𝗼𝗺𝗲𝗻𝗮𝗹 𝗰𝗼𝗺𝗺𝘂𝗻𝗶𝗰𝗮𝘁𝗶𝗼𝗻 𝗮𝗻𝗱 𝗽𝗿𝗼𝗷𝗲𝗰𝘁 𝗺𝗮𝗻𝗮𝗴𝗲𝗺𝗲𝗻𝘁 𝘀𝗸𝗶𝗹𝗹𝘀. 𝗜𝗻𝘁𝗲𝗹𝗹𝗶𝗴𝗲𝗻𝘁 𝗱𝗲𝘃 𝗽𝗿𝗼𝗰𝗲𝘀𝘀 𝗳𝗼𝗹𝗹𝗼𝘄𝗲𝗱 𝗯𝘂𝗶𝗹𝘁 𝘁𝗵𝗿𝗼𝘂𝗴𝗵 𝗼𝘁𝗵𝗲𝗿 𝗽𝗿𝗼𝗱𝘂𝗰𝘁 𝘀𝘂𝗰𝗰𝗲𝘀𝘀𝗲𝘀. ✅ 𝗦𝗰𝗮𝗹𝗮𝗯𝗹𝗲 𝘀𝗼𝗹𝘂𝘁𝗶𝗼𝗻𝘀, 𝗲𝗻𝘁𝗲𝗿𝗽𝗿𝗶𝘀𝗲-𝗿𝗲𝗮𝗱𝘆 𝗳𝗿𝗼𝗺 𝗹𝗮𝘂𝗻𝗰𝗵. ✅ 𝗨𝗦 𝗰𝗹𝗶𝗲𝗻𝘁 𝘀𝗽𝗲𝗰𝗶𝗮𝗹𝘁𝘆. Hi, I’m Andrew! I specialize in delivering polished SaaS apps consistently focused on earning revenue. 𝗜𝗻𝘃𝗶𝘁𝗲 𝗺𝗲 𝘁𝗼 𝘆𝗼𝘂𝗿 𝗽𝗿𝗼𝗷𝗲𝗰𝘁 𝗼𝗻 𝗨𝗽𝘄𝗼𝗿𝗸 𝗼𝗿 𝘀𝗲𝗻𝗱 𝗺𝗲 𝗮 𝗱𝗶𝗿𝗲𝗰𝘁 𝗺𝗲𝘀𝘀𝗮𝗴𝗲 𝗮𝗻𝗱 𝗶𝗳 𝘁𝗵𝗲𝗿𝗲’𝘀 𝗮 𝗹𝗶𝗸𝗲𝗹𝗶𝗵𝗼𝗼𝗱 𝗼𝗳 𝗮 𝗴𝗼𝗼𝗱 𝗳𝗶𝘁 𝘁𝗼 𝘄𝗼𝗿𝗸 𝘁𝗼𝗴𝗲𝘁𝗵𝗲𝗿, 𝗜’𝗹𝗹 𝗶𝗻𝘃𝗶𝘁𝗲 𝘆𝗼𝘂 𝘁𝗼 𝗯𝗼𝗼𝗸 𝗮 𝗰𝗼𝗺𝗽𝗹𝗶𝗺𝗲𝗻𝘁𝗮𝗿𝘆 𝗰𝗼𝗻𝘀𝘂𝗹𝘁𝗮𝘁𝗶𝗼𝗻 𝗰𝗮𝗹𝗹 𝘁𝗼𝗴𝗲𝘁𝗵𝗲𝗿. 🗣 𝗝𝗼𝗵𝗻 𝗠𝘂𝗹𝗹𝗲𝗻𝗵𝗼𝗹𝘇 - 𝗛𝗲𝗮𝗱 𝗼𝗳 𝗦𝗮𝗹𝗲𝘀, 𝗦𝘁𝗿𝗮𝘁𝗲𝗴𝗶𝗰 𝗘𝗻𝘁𝗲𝗿𝗽𝗿𝗶𝘀𝗲 - 𝗨𝗯𝗲𝗿 𝗘𝗮𝘁𝘀 ❝ Andrew is the most skilled freelancer and developer I have ever worked with, and I have worked with a lot. He was able to take very broad ideas and turn them into actionable insights and plans in a way I could never imagine was possible. Andrew is the best possible thing to happen to our business and the definition of a true professional. I could not recommend him enough. Anyone who has the opportunity to work with Andrew should consider themselves extremely lucky. ❞ I excel at expertly guiding the app dev process to max out your revenue-earning potential in contrast to your costs, and to steer you away from common SaaS app pitfalls. Client Outcome Examples: ⚡ amzalert.com (8-Figure Acquisition - Rebuilt In 4 Months) ⚡ launchcontrol.us (8-Figure Annual Recurring Revenue - ARR) ⚡ GuestBan.com (Concept-To-Live in 5 Months - 1M+ Monthly App Checkins) My support is based on hard-won successes built through more than a decade of SaaS app obsession. Most of my clients are: ☑️ Existing Businesses - Post-revenue ☑️ Solopreneurs & Small Teams - Wanting to build an MVP app ☑️ Funded Startups - Focused on turning funding into MRR ☑️ Existing Early Stage SaaS - Want to rebuild and scale up I’m the founder of a small, hand-picked team of talented humans. I’m personally involved in all projects, and we only employ senior developers and native English speakers from the US for project management and communication. My team and I are able to consistently reduce dev costs by about 30-40% by leveraging pre-built development frameworks for common app experiences like the user login or checkout, for example, while reserving valuable dev hours for truly custom functionality. Every project we build delivers: 📱Cross Device Compatibility - Desktop - Mobile - Tablet 📈 App Speed Optimization 🧩 Scaleable - Cost-Effective Feature Addition Potential 🛡️ Security 📊 User Analytics & Internal Dashboards 🌐 Multi-Language Localization 🤖 Quality Assurance - QA 📜 Paid User Subscription, Billing & Renewal Management Thanks for taking the time to learn more about me. Invite me to your project or send me a direct message if you’re interested in working together. Talk soon! Andrew Mace - Founder - Lean Engineering Highlights of the work I have extensive experience in includes: SaaS MVP • AI Automation • No-Code/Low-Code • Process Automation • RPA • .NET 8 • Python • AWS • Azure • Docker • Serverless • OpenAI / ChatGPT • Generative AI • Zapier • Make.com • UiPath • Power Automate • n8n • Bubble • Airtable • Stripe • PayPal • Twilio • Slack • Teams • REST APIs • Webhooks • SQL • PostgreSQL • Redis • Power BI • KPI Dashboards • ETL • Airflow • Real-Time Chat • Push Notifications • Subscription Billing • CRM Integration • Lead Generation Bots • Data Analytics • Digital Transformation • Workflow Automation • Rapid Prototyping

Hi, I'm David, a seasoned mobile app developer with extensive experience across diverse client bases, from individuals to Fortune 100 companies. Specializing in Xamarin, I am known for my unwavering dedication and ability to deliver under pressure, making me the go-to developer for mission-critical projects and tight deadlines. My portfolio showcases my proven track record of successful delivery.

Hi! I'm Tim, a U.S. based software developer with over 22 years of experience. I specialize in building high performance, interactive, graphical applications. These are primarily desktop applications with C#/WPF, or computer games using the Godot game engine. I'm capable of handling most visual applications (digital signage, kiosks, exhibits, simulations, etc) and non-visual, system level applications ( command line tools, utilities, automation, background services ). Services I offer: * Custom software development - Working from your specifications, I can build your app or game from the ground up, or take your existing code and modify it as needed. * Prototypes, Vertical Slices, and Minimum Viable Products("MVP") - I'll work with you to iterate on early designs, so you can test out your ideas and concepts rapidly. * UI design and workflow improvement - Is your user experience lacking? I can help you streamline and enhance the look and feel of your app. * Performance and code optimization - App lagging, stuttering, or eating up CPU? I excel at writing robust, high performance C# code. * Bug fixes - I'll identify and resolve defects in your software. * Code Audits / Code Refactoring - I'll look for "code smells", and transform your codebase into something thats clear and maintainable. Make no mistake, code quality is closely tied to the overall performance and reliability of your software! Whether you want to build something new, or you have an existing product that you want to improve... I can help you take your software to the next level. Ready to get started? Send me a message, and I'll get back to you as soon as possible. Looking for something not listed? Or perhaps you're not sure where to start? Send me a message. I'd be happy to assist.

Two Upwork client contracts delivered: Python parsing pipelines into Flask and SvelteKit handbook apps for a U.S. Coast Guard reference tool and an oil-and-gas safety handbook. Currently building the iOS/Android responder app for the same client (237 commits in two months). Solo Flutter app launching with a paid tier: 839 commits, 46 test files, ten months of focused work. Portfolio at neoreca.dev is itself a showcase, built with Astro 5, Tailwind CSS v4, and Supabase. I build web and mobile applications from scratch, handling everything from PDF parsing to UI to database to deployment. What I work with: Mobile: Flutter and Dart. State management with Provider, local databases with Drift/SQLite, GoRouter for navigation, RevenueCat for in-app purchases, Material Design 3. Web: Astro 5, SvelteKit 2 with Svelte 5 runes, React, Next.js, TypeScript, Tailwind CSS v4. Static sites and server-rendered apps deployed to Cloudflare Pages. Backend and data: Supabase (auth, row-level security, edge functions on Deno), Go (chi v5, raw SQL, Postgres 16), Python 3.12 data pipelines (Azure Document Intelligence, PyMuPDF, SQLite with FTS5 full-text search). Cloudflare Turnstile for bot protection. Desktop: Tauri + Rust + SvelteKit for local-first apps. What I've built: IMH Navigator (Upwork client, two contracts delivered): Web apps for navigating large emergency response handbooks. A 392-page Coast Guard handbook parsed into 362 sections, 322 acronyms, and 183 glossary terms, then deployed as a Flask demo for client review. Then a 273-page oil-and-gas handbook parsed into 171 sections and 58 structured role pages with parsed responsibilities, checklists, and Mermaid org charts, built with SvelteKit 2 and Svelte 5 runes. Six-step Python pipelines with audit regression checks on every rebuild. Both contracts closed cleanly. USCG IMH Responder App (Upwork client, in progress): Flutter app for Coast Guard responders. 237 commits in two months. ICS form wizards with jump-between-steps navigation, draft management with undo, haptic feedback, and embedded SQLite content shipped from the parsing pipeline. Film Development Timer: A Flutter app for film photographers with audio-guided timing, chemistry exhaustion tracking, push/pull processing, and a RevenueCat-gated paid tier with trigger-keyed analytics. 839 commits, 46 test files, ten months solo from concept to launch. Waitlist landing page built with Supabase, Cloudflare Turnstile bot protection, and an edge-function welcome email pipeline. Neosoft Wimbows 99 blog: A Windows 98 desktop simulation in React with draggable/resizable windows, real-time chat via Supabase, mini-games, a sound system, and a fake DOS prompt. Mirrored on Neocities. Distinct enough that it stands on its own as a portfolio piece. neoreca.dev: My portfolio itself. Astro 5, Tailwind CSS v4, custom scroll-triggered animation systems, two separate deployments (static portfolio plus SSR admin dashboard for waitlist analytics). Three visual contexts (cinematic dark, film-dev orange, Win98) sharing a single codebase. Personal projects that keep my range fresh: Finance Tracker (Go + SvelteKit + Postgres) and Synth Bench (Tauri + Rust + SvelteKit). I build with the stack I'll need next, not just the stack I already know. How I work: I write clean, well-structured code and communicate clearly about progress and decisions. I respond within 24 hours. I'm comfortable working independently on full features or slotting into an existing codebase. My current client engagement is a two-month-in active subcontract, so I'm available for additional fixed-scope or hourly work alongside it. See full technical write-ups for every project at neoreca.dev

I build custom C# / .NET software for businesses that need reliable desktop applications, internal tools, and practical workflow solutions. My main experience is in Windows desktop development and business software. I work with C#, WPF, MAUI, ASP.NET Core, Razor, MVC, MVVM, SQL, Entity Framework, and Web API, and I’m also interested in Blazor-based internal applications. I’m a good fit for projects involving internal tools, workflow systems, document generation, printing features, integrations, and software that supports day-to-day operations. I work well on MVPs, prototypes, and milestone-based projects where the goal is to turn a business need into a practical working solution. I can take ownership of a project, communicate clearly, and make practical decisions to keep development moving. I can also help refine requirements as the project evolves. In many business applications, the best solution becomes clearer during implementation, and I’m comfortable helping shape that process while keeping the work structured and aligned with the client’s goals. I’m especially interested in .NET applications for internal platforms, admin tools, business automation, and AI-assisted workflow solutions where the technology supports a real business need. I usually prefer fixed-price or milestone-based projects when the scope is clearly defined, because it keeps the process transparent and predictable for both sides. If you need help building, improving, or supporting a .NET desktop application, internal business tool, or custom software solution, I’d be glad to discuss your project.