Off-the-shelf apps only get a Shopify store so far. If you’re hitting the limits of what the App Store can offer — bespoke checkout logic, inventory automation, custom customer portals, or integrations with internal systems — you need a Shopify custom app built specifically around your operations. By Design UK builds these apps for UK merchants at fixed prices, with AI-accelerated development that keeps timelines short and costs predictable, and with full source code ownership handed to you on delivery.
We sit in the space between hiring a freelancer and briefing a full agency. You get dedicated, senior-level development without the unpredictability of a solo contractor or the overhead and opacity of a large agency retainer. Every Shopify build is scoped with a fixed price up front, so there are no surprise invoices as the project progresses.
A custom Shopify app is any bespoke functionality built to your store’s exact specification rather than adapted from a generic marketplace listing. Typical projects we deliver include:
These are the kinds of projects covered under our wider Shopify development services, and for stores that eventually outgrow Shopify entirely, we also handle full SaaS development for standalone platforms.
Shopify custom app builds through By Design UK typically range from £499 to £18,999, depending on scope. A small, single-purpose app — such as a bespoke shipping rule or a lightweight admin integration — sits at the lower end. Multi-feature apps involving external API integrations, custom databases, or complex customer-facing logic sit toward the top of that range. Every quote is fixed before work begins, based on a clear scope document, so you know the total cost from day one rather than an hourly estimate that can drift.
Once your app is live, ongoing maintenance, monitoring, and iteration are available through Shopify support plans starting from £299/month, which cover updates as Shopify’s platform evolves and small feature additions as your store grows.
Freelancers are often the cheapest option on paper, but reliability is the real cost: single points of failure, inconsistent availability, and projects that stall if priorities shift elsewhere. Traditional agencies solve the reliability problem but introduce new ones — long discovery phases, opaque day-rate pricing that balloons beyond the original quote, and slow decision-making layers between you and the developer actually writing the code. Many agency contracts also leave the client with limited rights to the code they’ve paid for.
By Design UK is structured differently. You get a small, senior UK-based team, fixed pricing agreed before work starts, direct communication throughout the build, and full ownership of the source code once the project is delivered — no licensing restrictions, no vendor lock-in.
We don’t just build Shopify apps — we build and operate our own production software. Tackly.co.uk is a live multi-toolkit SaaS platform, designed, built, and maintained by our team, serving real users daily. It’s a direct demonstration of the same engineering standards, API architecture, and reliability practices we bring to every Shopify custom app project. If you’d like to see our broader portfolio and team background, visit our about page.
Ready to scope your project? Get in touch and we’ll come back with a fixed quote, usually within a few working days.
Yes. Every project delivered by By Design UK includes full source code ownership handed over on completion, with no ongoing licensing fees or restrictions.
Most Shopify custom apps take between two and eight weeks depending on complexity, thanks to our AI-accelerated development process. Timelines are agreed upfront as part of the fixed-price scope.
Yes, we offer ongoing Shopify support plans from £299/month covering monitoring, platform updates, and minor feature iterations, so your app keeps working reliably as your store grows.
Neither in the traditional sense. We’re a UK-based development team positioned between the two, offering fixed pricing, direct senior developer access, and full code ownership without freelancer risk or agency overhead.
By Design UK, Office 13, 25 Mollison Avenue, Enfield, EN3 7NJ. Email: info@bydesignuk.co.uk.
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