When Shopify isn't enough, a custom retail or e-commerce app gives you control over the full customer experience. Here's what to build and what it costs.

Most retail businesses don't need a custom-built e-commerce app — Shopify, WooCommerce, and similar platforms handle the fundamentals well and have an enormous ecosystem of plugins.

Custom development makes sense when your product or business model doesn't fit the standard mould: subscription boxes with custom rules, B2B ordering with account-specific pricing, marketplace models with multiple sellers, or a retail app deeply integrated with a physical store's POS and inventory system. When the off-the-shelf solution requires more workarounds than it solves, custom starts to make sense.

Here's what a custom retail or e-commerce app typically needs.

Payments

One-off payment processing via Stripe handles standard transactions — credit card, Apple Pay, Google Pay, buy now pay later. For retail, the payment flow needs to handle refunds, partial refunds, and store credit gracefully.

For businesses with complex discount logic — tiered pricing for wholesale customers, volume discounts, member pricing — the discount rules need to be built into the pricing engine rather than applied as coupon codes.

Subscription and recurring billing

If your model includes subscription boxes, auto-replenishment, or recurring orders, subscription billing handles the recurring payment logic: charging on a schedule, managing pauses and skips, and handling failed payments without immediately cancelling the subscription.

This is where custom development often has the most advantage over Shopify — subscription logic that involves variable quantities, mix-and-match products, or customer-configurable schedules is difficult to implement cleanly in off-the-shelf tools.

Customer accounts and profiles

User profiles store order history, saved addresses, payment methods, and preferences. For B2B retail — where business customers have account numbers, credit limits, and specific pricing tiers — profiles store this commercial relationship alongside the personal details.

Social login (Sign in with Google, Apple) reduces friction at signup for consumer-facing apps, where every extra step in registration costs conversions.

Push notifications and re-engagement

Push notifications are one of the highest-ROI features in retail apps. Order status updates ("your order has shipped, tracking number: ...") are expected. Re-engagement messages ("items in your cart are selling fast") and back-in-stock alerts are valuable when used sparingly.

The open rate on push notifications is typically 3–5× higher than email, making it the most effective channel for time-sensitive retail communication.

Admin panel and inventory

Someone needs to manage the catalogue, process orders, and handle exceptions. An admin panel built for the operations team — order management, inventory updates, customer lookup, refund processing — is as important as the customer-facing app.

For businesses with a physical store as well as an online presence, the admin panel needs to reflect both channels accurately. Real-time inventory that prevents overselling across channels is a common requirement.

Analytics dashboard

Analytics dashboard gives the business visibility into what's selling, who's buying, and how customers are behaving: conversion rates, average order value, repeat purchase rate, cart abandonment. These metrics drive decisions about product range, pricing, and marketing spend.

For businesses coming from Shopify, replicating the analytics they're used to — and extending it with business-specific metrics — is often a key requirement.

GST and tax

Australian retail needs correct GST calculations — 10% on taxable goods, exempt on fresh food and some medical products. For businesses selling internationally, Stripe Tax can automate multi-jurisdiction tax calculation (VAT, US sales tax) without manual rule management.

What does it cost?

A custom e-commerce app — product catalogue, payments, customer accounts, order management, push notifications, admin panel — typically runs $25,000–$55,000 AUD depending on catalogue complexity, subscription logic, and integration requirements.

The app cost calculator lets you estimate your specific build.

Questions to ask before you build

Are you sure Shopify won't work? The honest answer for most retail businesses is that Shopify solves 80% of the problem, and the 20% that doesn't fit can be handled with custom development on top of Shopify rather than a full custom build.

What's your B2C vs B2B split? B2B ordering apps — with account-specific pricing, purchase order workflows, and net terms — are very different from consumer retail and significantly more expensive to build.

What does your inventory management look like? If inventory is tracked in an existing system (a POS, a warehouse management system, an ERP), real-time sync between that and the e-commerce app is a critical integration to scope carefully.

How important is mobile vs desktop? A native iOS/Android retail app is a larger investment than a mobile-optimised web app. Define which you need and why before committing to the build.

Code Workshop

What does a retail or e-commerce app need?