01
Admin UI for internal ops
Clear admin screens for the tasks your team handles every day.
Custom Shopify apps when the App Store is not enough.
Fyntri builds private and custom Shopify apps for UK merchants who need Admin workflows, data sync, or store logic that off-the-shelf apps do not cover. Custom with a written estimate first. Theo Analytics is our public App Store product. This page is for apps we build on your store or Partner account.
- Private or custom
- Written estimate first
- Theo as shipped-app proof
App Store app vs private app vs theme code.
We will tell you if a £5,000 Standard branding pass or an App Store install is enough. Custom apps are for the gap.
| Option | Use when | Avoid when |
|---|---|---|
| App Store app | Common problem, maintained vendor | Your workflow or data needs do not fit the app |
| Private / custom app | Your workflow, your ownership | You only needed a theme section |
| Theme / Liquid only | Presentation and OS 2.0 sections | Needs webhooks, cron, or external API |
What we typically build.
Examples of custom app work I can help with. Checkout changes depend on your Shopify plan and the agreed project scope.
02
Webhook-driven jobs
Respond to order, stock and privacy-request notifications, with retries and alerts if processing fails.
03
Scheduled jobs
Reports, exports and reconciliation that run without someone clicking.
04
Metafields and metaobjects
Custom product and content fields your team can manage in Shopify.
05
Connectors
Into ERP, 3PL or supplier feeds when the App Store connector is wrong.
06
Checkout Extensibility and Functions
Custom when they fit the plan and the problem. Plan limits confirmed in discovery. Not sold as Standard.
How we work.
We agree what you need, put the price and scope in writing, and start after you approve.
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01
Agree the outcome
We write what “done” means for the named scope before any work is booked.
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02
Written estimate
A written quote for that scope.
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03
Approve and book
You approve the estimate. The work happens inside that written scope.
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04
Change orders in writing
Anything new gets a written change order before work starts.
Delivery checklist.
These land in the written scope before work is booked.
- API surface and versionWhich Shopify APIs, and which Admin GraphQL version you will run.
- EnvironmentsDev store first, then production, with a clear cutover.
- Auth modelCustom app on your store, or Partner app, matching who owns and maintains it.
- Monitoring and errorsAlert paths so breaks surface without a customer complaint.
- HandoverRepo access, runbook, and who gets alerted after launch.
Shipped-app proof, not this page’s offer.
Theo Analytics is Fyntri’s Shopify app: six email reports, Free / Pro / Business, listed as Theo Sales & Stock Reports. It proves we ship and maintain App Store software. Need reports? Go to Theo. Need something built for your ops? Stay here.
- Email firstThe report lands in your inbox. That is the product.
- ShortA few numbers that change what you do today.
- Built for ShopifyInstalls from the Shopify App Store and reads your store data.
Custom Shopify app development, answered.
Cost, public vs private apps, Theo, ownership, Checkout Extensibility and maintenance.
How much does custom Shopify app development cost?
Custom app work is quoted in writing after discovery. Small apps may be a short build. Connectors and Admin suites take longer.
Do you build public App Store apps for clients?
Possible, but most client work is private or custom on their store. Public App Store apps need listing, review, and ongoing maintenance scoped separately.
Is Theo Analytics available as a custom build for our brand?
Theo is our product. We do not white-label it as a common offer. We can discuss related reporting apps as Custom if the scope is different.
Private app or custom app?
Shopify’s current model uses custom apps installed on a store (and Partner apps for distribution). We pick the install model that matches ownership and who maintains it. Exact labels go in the written scope.
Is custom app work inside the £5,000 Standard setup?
No. Standard covers up to 3 approved App Store apps configured (settings, not custom code). Custom apps are quoted separately.
Who owns the app?
You do, when built for your store or Partner account under the written scope. Theo remains Fyntri’s product.
Can you extend Checkout?
Checkout Extensibility and Shopify Functions are Custom when they fit the plan and the problem. We confirm plan limits in discovery and quote in writing.
Will you maintain the app after launch?
Handover includes a runbook. Ongoing care is quoted as Custom when you need it, with hours and scope written down. It is not part of Standard.
Let’s make
your next move
a good one.
A new store. A fresh start.
A Shopify problem worth solving.
Independent developer. Shared ambition.Built with care, in the UK.