Mobile commerce apps built on your store's API
A customer shopping app succeeds or stalls on the API underneath it, not on the screens. This page plans a mobile commerce app built on an existing store or marketplace API: the audit that comes first, sign-in, catalogue and search, cart and checkout, notifications, order tracking, returns, and the phased delivery that gets a working app to a first release without rebuilding the API from scratch.
Submit a project See the related serviceReviewed by David Nguyen (CEO) · Updated 1 Oct 2026
Why the API comes first
An app that calls an API designed only for a web storefront usually hits gaps: no endpoint for saved addresses, no webhook for order status changes, pagination built for a desktop page size, or a checkout flow that assumes a browser redirect a native app cannot follow cleanly. Starting app design before the API audit means discovering these gaps mid-build, when they are expensive to fix. The audit is the first milestone, not a formality before the "real" work starts.
What the API audit covers
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Authentication
Does the API support token-based sign-in, including social sign-in, that a mobile client can use safely?
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Catalogue and search
Can the API serve paginated, filterable catalogue and search results sized for a mobile screen?
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Cart and checkout
Does checkout complete without a browser redirect the app cannot embed cleanly?
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Order and notification events
Can the app receive order-status changes as push events, or only by polling?
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Returns and account data
Are returns, order history and address book exposed, or only available in an admin panel?
Gaps found here become API work in the plan, scoped and estimated before the app's screens are designed around them.
The target workflow
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API audit
Confirm what the existing store or marketplace API already supports and list the gaps against the sections below.
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Sign-in
Social and standard sign-in, with tokens the app can refresh without forcing a repeated login.
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Catalogue and search
Category and brand browsing, smart search and product comparison, sized and paginated for a mobile screen.
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Cart and checkout
A persistent cart with coupons and shipping costs, and checkout that completes inside the app.
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Notifications
Push notifications for order updates, flash sales and back-in-stock and drop alerts, with an in-app notification panel as the fallback.
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Order tracking and returns
Order tracking, returns with photos, cancellations and invoice download, backed by the API events the audit confirmed.
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Phased delivery
A first release covering sign-in, browse, cart and checkout; later phases add wishlist, reviews, dark mode and offline browsing once the core path is proven.
Where this differs from running the marketplace itself
Marketplace and classifieds operations runs the marketplace operation from a listing being posted to a deal closing: vendor approval, moderation, fulfilment routing. This page is the companion shopping app that sits on top of that operation's API, or on a standalone store's API, once the operation itself is running. A project that needs both is usually sequenced with the operation first, since the app's API audit depends on endpoints the operation defines.
Data and integrations
The app calls the store or marketplace API for every object it shows: catalogue, cart, order, account and notification. Netbase's mobile SDK interface components connect a client app to that API; where the API itself is being built or extended alongside the app, it is commonly a Laravel backend, and the underlying choice between a coupled storefront and an API-first architecture is covered on headless versus traditional e-commerce.
- Netbase builds the companion customer shopping app on Android, with iOS in the extended scope.
- Most projects are agreed as fixed-scope contracts after discovery, with milestone-based arrangements also available.
- Netbase's delivery lifecycle: discovery and strategic alignment; team assembly and architecture planning; agile execution with outcome-based milestones; modular components; training and rollout; ongoing support. On an app project, discovery closes once the API audit's gap list is agreed with the team that owns the underlying store or marketplace.
Delivery modules
- API audit and gap list: endpoints, authentication, pagination and event support checked against the sections above.
- Sign-in and account: social and standard sign-in, address book, order history.
- Catalogue and search: category and brand browsing, smart search, product comparison.
- Cart and checkout: a persistent cart with coupons and shipping costs, completing inside the app.
- Notifications and tracking: push notifications, an in-app panel, order tracking and returns with photos.
- Phased release plan: a first release scope and the later phases it defers.
Rollout
Stage one is the API audit and gap list, scoped as its own milestone so gaps are known costs rather than mid-build surprises. Stage two builds sign-in, catalogue, cart and checkout, the path a first release needs end to end. Stage three adds notifications and order tracking once the core path is stable. Stage four, often a later phase, adds wishlist, reviews, dark mode and offline browsing.
Risks
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Checkout assumes a browser
A checkout flow built only for web redirects breaks inside a native app and has to be rebuilt, not patched.
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Notifications treated as an afterthought
Push infrastructure and the events that trigger it need designing with the API, not bolted on after the app ships.
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A first release scoped too wide
Shipping wishlist, reviews and offline browsing before sign-in, browse and checkout are proven delays the release that actually matters.
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Store listing left to the end
App-store review and listing are a separate workstream from the engineering scope and need their own time in the plan.
How success is measured
Track API gap count closed before app development starts; time from kickoff to a working first release covering sign-in, browse, cart and checkout; crash-free session rate once live; and push notification delivery and open rates once that phase ships. These are your numbers, on your app and your API.
Who runs this workflow
The workflow fits a retailer or marketplace operator with a working store or marketplace API who wants a companion customer app: a fashion or general retail storefront, or a multi-vendor marketplace where buyers currently only browse on the web. It does not fit a business with no storefront or marketplace API yet, where the storefront itself, covered by custom product engineering, is the first project.
Proof from delivery
For RB Marketplace, an English-first multi-vendor marketplace for West Africa, Netbase built the customer shopping app on the marketplace's own API: Android, with iOS in the extended scope, push notifications for order updates, flash sales, back-in-stock and drop alerts with an in-app notification panel, Google, Facebook and Apple sign-in, category and brand browsing, smart search, product comparison, a persistent cart with coupons and shipping costs, checkout through a secure web view, order tracking, returns with photos, cancellations and invoice download, a server-synced wishlist, address book, reviews, dark mode and offline browsing, with 45 or more screens delivered in six phases from kickoff and API audit to QA and handover.
See the RB Marketplace mobile app record
Representative commerce projects for clients that are not named include Magento stores with companion Android and iOS apps for a women's fashion retailer in the Netherlands, an omnichannel fashion retailer in Nigeria and a parts and equipment seller, and the loyalty and reward shop platform built with mobile SDK interface components for client apps on a headless multi-store reward shop platform.
An agreement of confidentiality covers the engagement, no client is named, and no result is claimed.
Keep Reading
This record sets out what was delivered on each side, what deliberately stayed in the web panel, and what the project documents do not support.
Keep ReadingCommon questions
Because an app's screens are only as good as the data and events behind them; finding a missing endpoint after the screens are designed costs more to fix than finding it first.
Netbase builds the customer shopping app on Android, with iOS in the extended scope; your proposal states which platforms are in the first release.
The audit flags this as a gap, and adding event support, typically a webhook the app subscribes to, becomes part of the scoped work.
That depends on the payment provider and the existing API; the audit states what is possible and what requires a secure web view instead.
Sign-in, catalogue, cart and checkout ship first; wishlist, reviews, dark mode and offline browsing are typically later phases once the core path is proven.
Services behind this solution
Custom product engineering for a bounded release outcome
One defined release of your product, built to named outcomes and handed over with acceptance evidence.
Learn More
Scope this app
Bring the store or marketplace API you already run, or the platform it will be built on, and the features you consider essential for a first release. Custom Product Engineering is the commercial route; the marketplace matching and quotation guide covers the request-and-quote workflows an app sometimes needs to surface, and headless versus traditional e-commerce covers the architecture choice behind the API itself. Other workflows are listed under solutions. Submit a project with the API and the platforms you need. OutsourcingVN is operated by Netbase JSC and is Netbase's own outsourcing-services platform.