Shopify App and Store Development

Shopify app development is building software that plugs into a Shopify store through Shopify’s APIs, extensions and Functions, to add features the store does not have out of the box. Xtnd builds custom Shopify apps and Shopify stores from Nasr City, Cairo, for merchants in Egypt, Saudi Arabia, the UAE and the wider Gulf.

We also build and run our own Shopify app, Cartsaver, so we know the platform from the merchant side and the developer side.

When does a store need a custom Shopify app?

A store needs a custom app when the Shopify App Store has nothing that fits, when several apps would be needed to do one job, or when the store must connect to a system of its own. Common cases are a local courier, an ERP, a WhatsApp flow or checkout rules that are specific to one market.

Before we build anything, we check whether a theme change, Shopify Flow or an existing app already solves the problem. A custom app is code you have to host and keep current, so it should earn its place.

What can Xtnd build on Shopify?

We build public apps for the Shopify App Store, custom apps for a single store, and the extensions that put an app’s features inside Shopify itself. We also set up and customise Shopify stores, so one team can handle the store and the code that extends it.

What that covers in practice:

• Admin apps with their own settings and dashboards inside the Shopify admin.
• Shopify Functions that change checkout logic, such as which payment methods a customer sees.
• Theme app extensions that add blocks to the storefront without editing theme code.
• Admin extensions such as a block on the order page.
• Shopify Flow triggers so merchants can automate what happens next.
• Integrations with outside services through webhooks and the Shopify Admin API.
• Store setup: themes, Arabic and English content, shipping zones and payment settings.

What has Xtnd built on Shopify?

Our clearest proof is Cartsaver, our own Shopify app. It is listed on the Shopify App Store under the developer name Xtnd and holds the Built for Shopify badge, which Shopify gives to apps that meet its highest standards for performance, design and integration. Its back end runs on Laravel.

See the Cartsaver listing on the Shopify App Store or visit cartsaver.net.

Custom app, public app or an existing app: which one fits?

Pick an existing app when one already does the job well. Pick a custom app when the need is specific to your store or your systems. Pick a public app when you want to sell the solution to other merchants. The table shows the trade-offs, so you can see which route matches your budget, timeline and plans.

	Existing App Store app	Custom app (one store)	Public app (App Store)
Best for	Common needs	Needs specific to your store or systems	A product you sell to many merchants
Who owns the code	The app’s developer	You	You
Shopify review	Already listed	Not required	Required before listing
Running cost	Monthly subscription	Hosting and maintenance	Hosting, maintenance and support
Fit to your process	You adapt to the app	Built around your process	Built for many stores, so more settings
Billing	Paid to the app developer	None	Through Shopify’s billing for apps

How does a Shopify app project work?

A project moves from a written scope to a working app in a development store, then to your live store or the App Store. You see progress at each step and approve it before we move on, so nothing reaches your customers without your sign-off.

1. Discovery call. We learn the problem, the store and any systems the app must talk to.
2. Written scope. Features, Shopify surfaces, data the app reads and writes, and what is out of scope.
3. Design. Admin screens and any storefront parts, in English and Arabic where needed.
4. Build in a development store. You get access to test as features land.
5. Testing. Real orders, edge cases, mobile, and both languages.
6. Launch. Install on your store, or submit to the Shopify App Store for review.

Example: connecting a Shopify store to a local courier

This is an illustrative scenario, not a client project. A Cairo fashion brand on Shopify ships through a local courier that has an API but no Shopify app. Staff copy every order into the courier’s portal by hand, and customers ask on WhatsApp where their parcel is.

A small custom app could fix both problems:

1. When an order is paid or confirmed, the app creates the shipment in the courier’s system through a webhook.
2. The courier’s tracking number is saved on the Shopify order and the order is marked fulfilled.
3. When the courier reports a status change, the app updates the order and sends the customer a short message.
4. An admin block on the order page shows the shipment status, so staff stop switching between systems.

The app is private to that store, so it needs no App Store review. The main ongoing work is keeping up with Shopify’s API versions and any changes to the courier’s API.

What affects the cost and timeline of a Shopify app?

Cost and timeline depend on scope more than anything else. The number of features, the Shopify surfaces involved, outside systems, Arabic support, and whether the app goes on the App Store all add work. We send a quote once the scope is clear, so you know what you are paying for before we start.

The main factors:

• Features and screens. Each setting, report and workflow adds design and testing time.
• Shopify surfaces. Functions, checkout extensions, theme blocks and admin blocks each need their own build and testing.
• Outside systems. Couriers, ERPs and messaging APIs bring their own limits and documentation.
• Public or custom. A public app needs billing, onboarding, App Store review and support.
• Hosting. Where the app’s server runs, and how often the app needs updates.

For a wider view of platform choice and cost, see our e-commerce website development page. If your store runs on WordPress, see WooCommerce development. For a platform that does not fit Shopify at all, see custom Laravel development. Related reading: Shopify OTP verification for COD orders and Shopify vs WooCommerce vs Magento vs BigCommerce.

Frequently asked questions

What is the difference between a custom app and a public Shopify app?

A custom app is built for one store and installed through a private link. It is not listed on the Shopify App Store and does not go through public app review. A public app is listed on the App Store, can be installed by any merchant and must pass Shopify’s review first.

Can you add features to my store without building a full app?

Often, yes. Some needs are met by theme changes, Shopify Flow, metafields or an existing app with the right settings. We check those options first and only suggest a custom app when it is the simpler or more reliable route.

Do you build Shopify stores as well as apps?

Yes. We build Shopify stores as well as Shopify apps. If a store needs a feature that no existing app covers well, we can build it as a custom app or extension.

Can a Shopify app work with WhatsApp?

Yes. Our own app, Cartsaver, works through the official WhatsApp API, as its Shopify App Store listing describes. A custom app can use Meta’s WhatsApp Business API for your own flows, such as telling customers or your team when an order changes.

How much does Shopify app development cost?

It depends on scope: how many features, which Shopify surfaces the app touches, the outside systems it connects to, and whether it is public or custom. We send a quote once we understand what the app must do.

Where does a custom Shopify app run?

A Shopify app runs on its own server, not inside Shopify. The app reads and writes store data through Shopify’s APIs. That server has to be hosted and kept current, because Shopify releases new API versions on a regular schedule.

Talk to us about your Shopify project

Tell us what your store needs on WhatsApp or through the contact form.