Hong KongApp & Custom Software Development in Hong Kong
Software development for Hong Kong. We build secure, scalable mobile apps and web platforms for Asia's premier financial hub and Greater Bay Area gateway.
App369 is a founder-led software studio based in Miami, Florida. Simon builds custom mobile apps, web platforms and AI features for businesses in Hong Kong and beyond, working remotely on Eastern Time.
- Fiverr
- 5.0 · 127 reviews
- Own product
- Workspace369
- Fixed-price offers from
- $450
Same fixed prices wherever you are
Fixed scope, fixed price, paid upfront. The work happens in writing; no call needed.
- App Fix Ticketfrom $450One reproducible bug in an existing mobile or web app, diagnosed and fixed.
- AI-Built App Rescuefrom $450A Lovable, Bolt or Cursor app checked end to end in 3 days, then its worst problems fixed at a fixed price.
- Web App MVP Sprintfrom $6,000A scoped web app MVP in Vue/Nuxt or React, with a fixed quote after a $450 written scoping.
- Monthly Dev Subscriptionfrom $1,495/monthOne development request at a time, most back in about 2 business days. Pause or cancel anytime.
Why App369
Why Hong Kong Businesses Choose App369
What Hong Kong teams should know before working with App369.
Serving Hong Kong Island, Kowloon, New Territories, and the Greater Bay Area corridor to Shenzhen
Focus on fintech, trading platforms, and digital banking
Focus on HKMA fintech sandbox, SFC licensing requirements, and PDPO (Personal Data Privacy Ordinance) compliance
Proximity to Shenzhen hardware ecosystem for IoT and connected device software development
What Simon builds
Software Development Services in Hong Kong
From Central's financial district to Cyberport and Science Park, we deliver software engineered for Hong Kong's fast-paced, regulation-driven financial markets.
Mobile Apps
iOS and Android apps built with Flutter from one codebase, from concept to App Store launch.
- iOS & Android
- Cross-Platform
- App Store Optimization
- Maintenance & Updates
Web Development
Fast websites and web applications, built for search and for phones first.
- Custom Design
- E-Commerce
- SaaS Applications
- SEO Optimization
Custom Software
Internal tools, integrations and back-office systems engineered around how your team already works.
- Enterprise Development
- API Integration
- Cloud Migration
- Technical Consulting
How it works
The 4-Phase Development Process
A written scope and four clear phases keep Hong Kong projects predictable.
Discovery
Understanding your vision, goals, and market requirements through stakeholder interviews and competitive analysis.
Design
Creating clear UI/UX with interactive prototypes you can click through before the build starts.
Development
Building with Flutter, Vue.js, Node.js, and GCP using 2-week Agile sprints with weekly milestone reviews.
Launch
Deployment to production with crash and uptime monitoring and ongoing maintenance.
Technologies
- Flutter
- TypeScript
- Node.js
- GCP
- Firebase
- Vue
- JavaScript
- Python
Questions
Frequently Asked Questions
How long does a typical project take?
It depends on scope. As a rough guide, a marketing website takes 4-8 weeks, a web application 2-4 months, and a mobile app 3-6 months. Every Hong Kong project starts with a written scope and milestone plan, so you know the timeline before any build work starts.
Do you provide ongoing support?
Yes. After launch App369 offers maintenance that covers bug fixes, iOS and Android OS updates, security patches, dependency upgrades and small feature work, so your Hong Kong app keeps working as the platforms change.
What's your pricing model?
Fixed-price offers are paid in full before work starts, at the prices published on the fixed-price page. Larger builds start with a paid scoping and are then quoted in writing, with their payment schedule, and start only with your yes.
Can you work with existing projects?
Yes. Simon takes over existing codebases, especially Flutter and Firebase apps, for code audits, bug fixes, new features and migrations. Hong Kong businesses with an app that stalled or a developer who left can start with an audit before committing to a larger build.
What technology do you use?
Mostly Flutter for iOS, Android and web apps from one codebase, Firebase and Google Cloud for backends, and Vue/Nuxt for websites. For AI features Simon integrates large language models for assistants, document extraction and automation.
Your Development Partner
Simon Dziak
As founder of App369, I personally oversee every project App369 takes on, from scoping to launch. I build with Flutter, Firebase and Google Cloud, and I also built and run Workspace369, a client-management platform for freelancers and small businesses. Based in Miami, Florida, I serve clients across Hong Kong and nationwide.
Start Your Hong Kong Project
Fiverr reviews / 95 on app work
What buyers said about working with Simon
“Working with Simon has been an absolute pleasure. He’s not only incredibly skilled with his code, but he also brought so much care and attention to detail, especially when creating a custom section template for my Shopify site. He made the entire process smooth and collaborative, and consistently went above and beyond to make sure everything looked and functioned beautifully, very much the way I've envisioned. Highly recommend him for anyone looking for thoughtful, top-notch development support!”
A buyer in China, April 2025. Custom order on Fiverr “Very detailed and professional. Understands full scope of project before advancing and has honest but critical feedback. such a pleasure with consultation and can't wait to get started.”
A buyer in the United States, July 2024. Custom order on Fiverr “Had a great consultation with Szymon. He knows his stuff and I have a deeper understanding of how my new mobile app can work.”
A buyer in the United States, April 2024. Custom order on Fiverr
Read the whole story
- Sixteen five-star reviews from one buyer: mobile apps, app design and a Shopify store (Mark, United States)
- A large custom app build, delivered on the back end and the front end (A buyer in the United States)