Custom Web Applications
Web Applications
Fast, SEO-friendly web apps that work on every device. From internal tooling and analytics dashboards to payment portals and multi-tenant SaaS platforms.
Phát triển phần mềm theo yêu cầu
Custom Software Development
Web Applications · iOS & Android Apps · AI & Voice Integration
Techfusion company limited builds custom web applications, mobile apps and AI-powered systems for businesses, startups and individuals. We work in Vietnamese and English, hand over full ownership of the source code, and treat data privacy as a design decision rather than an afterthought.
What we build
We stay with the product from the first requirements conversation until it is running in production.
iOS & Android Mobile Apps
Mobile Applications
Smooth mobile apps on both iOS and Android. Native-feeling interfaces per platform, offline-first architecture and secure synchronisation whenever a connection is available.
AI & Voice Integration
AI & Voice Integration
Drawing on our own products (VieNeu-TTS, Kokoro-82M), we integrate speech synthesis, speech recognition, large language models (LLM, RAG) and automated assistants into your workflows.
Architecture, Security & DevOps
Architecture & DevOps
Load-tolerant system architecture, automated CI/CD pipelines, backups and security reviews — so the software complies with data protection rules (GDPR, Vietnam's Decree 13/2023/ND-CP).
Our stack
We pick stable, modern technologies with long-lived community support, and avoid risky dependencies.
Frontend & UI
React, Next.js, TypeScript, Tailwind CSS, Vue.js. Accessible interfaces that load fast and work in every browser.
Mobile
Swift & SwiftUI (native iOS), Kotlin & Jetpack Compose (native Android), Flutter and React Native for cross-platform builds.
Backend & Data
Node.js, TypeScript, Python (FastAPI, Django), Go, PostgreSQL, Redis, local SQLite, ClickHouse for analytics.
AI & Audio
OpenAI API, Claude API, on-device ONNX Runtime, Kokoro-82M, VieNeu-TTS, Whisper STT, Hugging Face Transformers.
A five-step process
Clear scope, continuous reporting, and a visible result at every stage.
STEP 01
Discovery & Analysis
We map the requirements, the audience and the technical risks, then agree on an approach and a detailed quote.
STEP 02
UI/UX Design & Architecture
Interactive design mock-ups, agreed user journeys, plus the system architecture, data model and API design.
STEP 03
Development & Testing
Built in sprints with automated tests, continuous integration and a shared preview environment on every release.
STEP 04
Deployment & Handover
We ship to your infrastructure and the stores, then hand over the full source code, documentation and accounts.
STEP 05
Warranty & Support
Technical support after launch, fixes for anything that surfaces, and continued work as your product grows.
Our commitments
We operate with technical quality, transparency and your interests as the priorities.
You own 100% of the source code
No vendor lock-in. We hand over the complete Git repository, architecture documentation and deployment guide.
Privacy & data security
Security-aware engineering, encrypted transport and storage. We sign a non-disclosure agreement before the work starts.
Bilingual VI / EN delivery
We communicate directly in Vietnamese or English, whichever suits you — convenient for local clients and international partners alike.
A properly registered company
Techfusion company limited is registered in Vietnam (company number 1001261052). Clear contracts, VAT invoices and full legal paperwork.
Frequently asked questions
Common questions we hear when clients start a custom software project with us.
What kinds of software do you build?
We focus on three areas: web applications (SaaS, admin dashboards, landing pages, internal portals), mobile apps (native iOS with Swift, native Android with Kotlin, or cross-platform with Flutter) and AI integration (voice assistants, large language models, speech recognition). We also advise on system architecture and security hardening.
Will we own the source code?
Yes. The full source code, technical documentation, database and access to the cloud services are transferred to you when the project is finished. You are free to use, modify and commercialise it.
How long does a project take and what does it cost?
Both depend on the feature complexity. A straightforward application usually takes three to six weeks, while more complex systems can run from two to four months. After the requirements discussion we send a detailed estimate broken down by delivery milestone.
Can we sign an NDA before starting?
Yes. We are happy to sign a non-disclosure agreement before you share any concept documents or business data.
Is there support after the handover?
Every project includes a warranty period for defects. After that you can opt for a maintenance package, or request new features as your needs evolve.
Ready to start your project?
Send us a short summary of your idea, your requirements or your technical questions. The Techfusion company limited team replies within one business day.