At some point, every growing Shopify business hits a limit. A theme edit isn’t enough. An off-the-shelf app is close, but not quite right. That’s usually the moment when a Shopify app becomes the clean solution.
This guide explains the difference between public Shopify apps (listed on the App Store) and custom apps (built for a single merchant). You’ll also learn what it takes to launch, what to watch for, and when an app is the right investment.
If you want to build an app, here’s our service page: Shopify App Development. If you’re deciding between app work and theme work, you can also compare with Custom Shopify Coding and Sections.
What is a Shopify app
A Shopify app extends what Shopify can do. Apps can add features to the admin, sync data with external systems, modify storefront behavior, create automations, or provide new workflows for merchants and customers.
Shopify’s developer documentation provides the core building blocks for app development, including authentication, APIs, and app distribution. External references: Shopify Apps overview, Shopify APIs.
Public apps vs custom apps
Public Shopify apps (Shopify App Store)
A public app is built for many merchants and distributed through the Shopify App Store. This route makes sense when you have a repeatable problem, clear value, and a market that will pay for it.
Typical characteristics:
- Designed for broad use across many stores
- Requires a strong onboarding flow and support process
- Often includes subscription billing and plans
- Must follow Shopify’s requirements for listing and review
External reference: App distribution and listing.
Custom apps (built for one merchant)
A custom app is built for one business, one workflow, one stack. This is often the fastest and cleanest way to solve operational needs like ERP sync, PIM rules, fulfillment logic, or internal tools.
Typical characteristics:
- Built for a specific store or organization
- Focused on integrations, automation, and efficiency
- Usually no public listing or App Store marketing
- Can be iterated quickly and tailored to the team
If your goal is a better storefront experience rather than back-office automation, a theme system may be the better ROI. See: Theme Development.
What Shopify apps can do (real examples)
- Integrations: connect Shopify to ERP, PIM, WMS, shipping platforms, marketplaces, or analytics tools
- Catalog automation: tagging, pricing logic, inventory rules, and merchandising workflows
- Customer experience: product customization flows, bundles logic, recommendations, gated content
- Admin tools: dashboards, bulk actions, support tools, internal approvals, custom workflows
For headless brands, apps can also support API-driven storefronts and custom infrastructure. See: Headless Shopify Development.
App Store launch basics
Launching a public app is not only about code. It’s about packaging, trust, and support.
1) Onboarding and UX
Merchants need to understand value fast. A public app should have a short onboarding flow, clear defaults, and safe fallbacks.
2) Permissions and data access
Request only the scopes you truly need. Over-requesting access is a common reason apps lose trust and fail review.
3) Billing and plans
If you monetize, you’ll likely use Shopify’s billing APIs. External reference: Billing for Shopify apps.
4) Review readiness
Public apps are evaluated for merchant experience, stability, security, and compliance with Shopify’s policies. External references: App Store requirements, App review process.
How to decide if you need an app
An app is the right move when:
- You need a workflow or integration that themes cannot solve cleanly
- You want a repeatable product you can sell to many merchants
- You want reliability and control instead of stacking multiple apps
- Your requirement touches the admin or complex data operations
If your need is mostly storefront layout and content flexibility, start with a Shopify 2.0 theme system and custom sections: Custom Coding and Sections.
How MoonImpact builds Shopify apps
We build apps with a product mindset and production standards:
- Clear scope and roadmap based on real merchant needs
- Stable architecture and API-first implementation
- Clean UX, onboarding, and error handling
- Performance, security, and upgrade safety as defaults
- Launch support for App Store readiness when needed
Start here: Shopify App Development or Contact.
FAQ
Do I need Shopify Plus to build a Shopify app
No. Apps can be built on standard Shopify plans. Shopify Plus may matter depending on your checkout customization needs or enterprise workflows, but it is not required for app development.
What is the difference between a public app and a custom app
A public app is distributed to many merchants through the App Store. A custom app is built for one merchant to solve a specific workflow or integration.
How long does a Shopify app take to build
Simple apps can take weeks. Apps with billing, complex integrations, and polished onboarding can take longer. Timeline depends on scope and review requirements.
Can you help with the App Store review process
Yes. We build toward review readiness and can help prepare requirements, onboarding, and compliance needs for submission.