You searched the app store and nothing fits
You need something specific. Maybe orders over a certain value must be checked by a manager before fulfilment. Maybe a product needs a price calculated from measurements the customer enters. Maybe order data has to reach an old stock system that no app has heard of. You have read app descriptions, tried a couple of trials, and each one does most of it but not the part that matters.
Somewhere along the way you came across the phrase "custom app" and a setting called something like "allow custom app development". Now you are wondering what it means and whether it is safe to switch on.
What the setting actually does
A custom app is an app built for one store, yours, rather than listed in the Shopify App Store. It talks to your store through the same APIs public apps use, but only with the permissions you grant.
Shopify needs the store owner to allow this before custom apps can be created, which is why the setting exists and why staff accounts often cannot switch it on. Shopify has been changing where and how custom apps are created, moving from the Develop apps screen in the admin towards its developer dashboard, so the exact buttons depend on when you read this. The principle stays the same: the owner authorises it, and each app requests specific access scopes, such as reading orders or writing products.
Allowing custom app development does not install anything or give anyone access on its own. It is the door being unlocked, not someone walking through it.
Why the missing feature hurts
When no app covers a need, the workaround is usually a person. Someone checks high-value orders by eye, calculates the price on a calculator and edits the cart, or retypes orders into the other system. The store looks automated from the outside while someone is quietly holding it together.
| Workaround | Hidden cost |
|---|---|
| Manual checks on certain orders | Delays, and orders slip through on busy days |
| Quotes by email for custom products | Customers who wanted to buy now go elsewhere |
| Retyping into another system | Errors, and one person the process depends on |
| Stacking several apps to approximate it | Monthly fees, conflicts and a slower store |
How we build your custom Shopify app
- Pin down the feature. We write down what should happen, when, for which orders or products, and what should happen when something is unusual. This is where most of the value is.
- Choose the right shape. Some needs are back-office only and use the Admin API and webhooks. Others need something on the storefront, which means a theme app extension, or on checkout, where what is possible depends on your Shopify plan and the available extension points.
- Request minimal scopes. The app asks only for the access the feature needs. If it only reads orders, it does not get permission to change products.
- Build and test on a development store first, with realistic data, before it touches your live store.
- Host it properly. The app runs on infrastructure such as AWS or Azure with logging, so failures are visible and webhooks are retried rather than lost.
- Hand over. You own the code. We document what it does, which scopes it holds and how to update it when Shopify releases new API versions.
Tell us early if a feature touches checkout. Checkout is the most locked-down part of Shopify, and we will check what your plan allows before promising a design.
Owning the feature instead of working around it
The feature works the way your business works, rather than the way a general-purpose app assumed it would. The workaround person gets their time back. You are not paying a monthly fee to a vendor for one feature, and you can change the behaviour when your process changes.
And because the app holds only the permissions it needs, you know exactly what it can and cannot touch.
Are you in this position?
- You have tried several apps and none does the specific thing you need.
- A person is doing a job by hand that the store should handle.
- You are combining two or three apps to approximate one feature.
- Your store needs to talk to a system no app supports.
- Someone mentioned custom app development and you are unsure what to switch on.