Services

Mobile app development, e‑commerce technology, and marketplace operations from Hanoi

For founders, companies, and sellers needing iOS or Android apps, seller tools, or storefronts on Amazon, Etsy, or Walmart. We build for partners with the same rigor as our own products: a dedicated team in Hanoi, a clear written scope, and real-world releases across global marketplaces. Learn more about our team or request a project scope.

01 · E-commerce technology

E-Commerce Technology for Sellers

Who it is for

Sellers and brands operating across multiple marketplaces who need a unified platform to manage products, orders, inventory, and reporting. Tested on our internal storefronts, access is rolling out to select partners in stages - contact us to request early access.

Services

  • Multi-channel product and listing management
  • Order, inventory, and shipment status synchronization
  • Automation for routine workflows: pricing, promotions, and reporting
  • Revenue, cost, and advertising performance analytics
  • Native integrations with your existing marketplaces and tools

Deliverables

  • Fully configured account integrated with your marketplaces
  • Complete onboarding and operational documentation
  • Direct access to the core product team

02 · Marketplace operations

Selling on Amazon, Etsy, and Walmart

Who it is for

Manufacturers, workshops, and brands looking to expand into the North American market through storefronts managed by CS Group.

Services

  • Platform-specific product and market research
  • Listings, imagery, and content tailored to marketplace standards
  • Targeted advertising and conversion rate optimization (CRO)
  • End-to-end order fulfillment and returns management (including POD)
  • SLA-compliant customer support across all marketplaces
  • Full policy and consumer protection compliance for Amazon, Etsy, and Walmart

Deliverables

  • Written marketplace feasibility assessment for your products
  • Structured partnership agreement (Supply, Co-development, or Distribution)
  • Standardized operating procedures and optional monthly performance reports

03 · Mobile apps

Mobile App Development

Who it is for

Founders and companies looking to build, launch, and scale iOS or Android apps, as well as partners seeking to co-develop or publish utility and lifestyle applications.

Services

  • Product discovery and detailed written scope
  • UI/UX design with interactive, clickable prototypes prior to development
  • Native (Swift, Kotlin) and cross-platform (Flutter, React Native) engineering
  • Backend architecture, API integration, authentication, in-app purchases, and push notifications
  • App Store & Google Play submission, privacy nutrition labels, and data safety compliance
  • Analytics setup, crash monitoring, App Store Optimization (ASO), and ongoing updates

Deliverables

  • 100% ownership of source code and design assets (as defined in scope)
  • Fully prepared store listings ready for submission
  • 30 days of post-launch support with flexible ongoing maintenance plans

How a project runs

Five steps, each with a clear, tangible deliverable.

  1. 01

    Scope

    Share your product vision via email. We reply with clarifying questions followed by a detailed written scope.

  2. 02

    Design

    Review and approve user flows and interactive prototypes before coding starts. For marketplaces: sample listings and an initial batch strategy.

  3. 03

    Build

    Development moves in two-week sprints, delivering a functional build at the end of each cycle.

  4. 04

    Launch

    We manage store submissions and resolve any platform review feedback.

  5. 05

    Operate

    Continuous monitoring, regular updates, and performance reporting on an agreed schedule.

Questions partners ask

Frequently asked questions before getting started.

Do you build for both iOS and Android?

Yes. We build both native and cross-platform apps. We recommend the optimal technology stack after our initial scoping call based on your product requirements.

How long does an app take?

An interactive prototype is typically ready within the first two sprints. Most apps reach store submission within a few months, with a detailed timeline provided in your project scope.

Who owns the code and the accounts?

For client projects, you retain 100% ownership of the source code, design assets, and store listings. Apps are published under your own developer account unless agreed otherwise. For co-developed products, ownership terms are clearly defined in the scope agreement before work begins.

Where are you, and how do you work with partners abroad?

We are based in Hanoi, Vietnam (GMT+7). We collaborate remotely with global partners in English and schedule meetings to conveniently align with your time zone.

How is pricing structured?

We offer fixed-price milestone billing per project scope or monthly retainer arrangements for ongoing work. No development begins without an approved scope and budget.

I already have an app or a store. Can you take it over?

Yes. We begin with a comprehensive code or store audit, document our findings, and agree on a transition roadmap before implementing any changes.

I make products in Vietnam. How do I start selling on Amazon through you?

Send us your product details, photography, unit costs, and monthly production capacity. We will evaluate marketplace fit in writing and propose an optimal partnership model before initiating work.

Tell us what you are building.

One email connects you directly with the team that scopes, designs, and launches your product. We respond to every inquiry within two business days.