Custom Shopify app or App Store: the 3-year cost comparison

The Shopify App Store has an app for almost anything, at $20 to $200 a month. A custom app costs thousands up front and nothing afterwards.

The maths looks obvious until you run it over three years, at which point it usually reverses. Here is how to decide, and the specific situations where each one is right.

Install from the App Store when

The app does what you need without configuration gymnastics. If it fits, it fits. A subscription app that handles your billing model, a review app that displays reviews, a shipping calculator that calculates your shipping. Buying is faster, cheaper, and someone else maintains it against Shopify's API changes, which happen twice a year and which you would otherwise be paying for.

The requirement is common. Reviews, email capture, loyalty points, upsells. Thousands of stores need these in nearly the same shape, which is exactly what an app is good at. You are buying the accumulated bug fixes of everyone who came before you.

You are testing whether you need it at all. Install, run it for two months, measure. If it earns its keep, keep paying or replace it later. If it does not, uninstall. A custom build cannot be uninstalled.

Your volume is modest. Under a few thousand orders a month, per-order app pricing rarely justifies a build.

Build custom when

Your process is genuinely yours. Not "we do it slightly differently", but a workflow that is part of why customers choose you. Custom pricing logic, a fulfilment routine tied to how you actually pack, an integration with the ERP you already run. Apps are built for the average of a thousand merchants and you are not the average.

You are paying for three apps to do one job. This is the clearest signal, and it is common. One app for the base function, a second for something the first cannot do, a third to bridge the two. Each is a subscription, each is a script in your storefront, and together they are usually slower and less reliable than one thing built properly.

App fees have crossed the line. Add up your monthly app spend for one workflow. Multiply by 36. Compare that to a build quote. At $150 a month you are spending $5,400 over three years for something you will never own and cannot modify.

You have hit a ceiling the app cannot raise. The app supports two pricing tiers, you need five. It syncs hourly, you need real time. There is no configuration screen for this and there never will be, because the app author is optimising for the other 999 merchants.

The data cannot leave your control. Regulatory or contractual constraints on where customer data sits, or who processes it.

Run the real numbers

Most people compare a monthly fee to a one-off quote and stop there. That comparison is missing things on both sides.

The app costs more than the subscription. Add per-order transaction fees, which scale exactly as you grow. Add the tier jump you hit at higher volume, which is where app pricing gets steep. Add the performance cost of its script on every page load, which is real and shows up in conversion. Add the switching cost if the app is discontinued, acquired, or triples its price, all of which happen.

The custom build costs more than the quote. Add maintenance, because Shopify releases two API versions a year and something will eventually need attention. Budget a few hours a year, not zero. Add the risk that your requirements change and the build has to change with them.

Honest rule of thumb from what we see: if a workflow costs under $50 a month in apps and works, keep it. Between $50 and $150, look at it once a year. Over $150 a month for one workflow, get a build quote, because the three year number is almost certainly in favour of building.

Public app, custom app, or theme extension

If you do build, there are three shapes and merchants are rarely told the difference.

Custom app. Built for your store, installed only on your store, never listed publicly. No review process, no App Store policies, no revenue share. This is what most merchants actually want when they say "custom app".

Public app. Listed on the App Store for anyone to install. Only worth it if you intend to sell it as a product. It brings a review process, ongoing policy compliance, and Shopify's revenue share. Building a public app to solve your own problem is doing considerably more work than the problem requires.

Theme app extension. For functionality that lives in the storefront rather than the admin, this is the modern way to add it. It loads through Shopify's own infrastructure rather than injecting a script tag, which means it does not carry the performance penalty that older app integrations do.

If someone quotes you a public app when you described an internal workflow, ask why.

The mistake that costs the most

Building custom to replace an app that was working fine, because it felt expensive.

A $29 a month app that does its job is $1,044 over three years. That is cheaper than almost any build, and it comes with someone else handling API updates. Replacing it with custom code is spending thousands to save a thousand, and taking on maintenance you did not have.

The apps worth replacing are the ones that do not quite fit: the ones you have configured into a corner, the ones you have stacked two more apps on top of, the ones where you have changed your process to suit the software. Those are the expensive ones, and the cost is not on the invoice.

A decision you can make in ten minutes

Take the workflow you are unsure about and answer four questions.

1. How much are you paying monthly, across every app involved in it?
2. Is any part of that workflow something a competitor could not copy by buying the same apps?
3. Have you changed how you work to fit the software?
4. Is there a hard limit you have already hit?

Two or more yeses on questions 2 to 4, or a monthly number over $150, and a build is probably right. Otherwise keep buying, and spend the money on inventory.

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We build custom Shopify apps, public and private, and we also tell merchants not to when an existing app would do. App builds run 4 to 8 weeks with a fixed price agreed up front, and you own the source code outright when it ships.

Book a 30 minute call and bring your app list. We will run the three year comparison with you, and if the answer is "keep the app you have", that is what we will say.