pdPurpledecks
Mobile apps and the systems behind them

The whole product. Not just an app.

Custom mobile app development services for founders building a new product: the native iOS and Android apps, the backend, the admin portal, the cloud, and the device the app talks to. Designed and built by one senior team. No offshore hand-off.

Talk to an engineer See the work →
PURPLEDECKS · EST. 2012 · 53.7°N 7.8°W · IRELAND · EU
§ 01 · The product

The whole product, built as one thing.

What we build · lift it whole
We design and build custom mobile apps and the systems behind them: native iOS and Android apps, or React Native where it fits, the backend with the real business logic in it, the admin portal your team runs the product from, the cloud infrastructure it all runs on, and the integration to the device. One senior team designs it, builds it, tests it, ships it and stays on it. We don't subcontract product delivery.
The stack · plain

Mobile: iOS and Android, native, and React Native. Web: React and Next.js. Backend: Node.js and Python, with PostgreSQL most often. Cloud: AWS and Google Cloud, with Docker, Kubernetes, Terraform and OpenTofu. Devices: Bluetooth Low Energy, firmware integration, serial, USB, low-power links and wifi.

§ 02 · Who does what

One team, and it's the team you talk to.

The job
Who does it
What you get
Design and UX
Our own design team, before the build
The user research, the UX and the screens, done by people in the same room as the engineers.
The app
Senior engineers
Native iOS and Android, or React Native.
The backend and the admin portal
The same team
The backend with the business logic in it, and the portal your team runs the product from.
The cloud
The same team
AWS or Google Cloud, built as code, in your accounts, so it can be rebuilt and it's yours.
QA
Our own QA people, in the build from the start
Testing through the build, not bolted on at the end.
Shipping to the stores
We do it
We build the CI/CD that ships each release, and we deploy on your accounts, App Store and Google Play, in your name.
Ownership
Done from day one, not written into a contract
The keys, the accounts, the domain and the code, in your name from the start. We have seen too many companies find out late that they don't own parts of their own product.
After launch
We stay on it
See §05.
Design and UX
Who does it

Our own design team, before the build

What you get

The user research, the UX and the screens, done by people in the same room as the engineers.

The app
Who does it

Senior engineers

What you get

Native iOS and Android, or React Native.

The backend and the admin portal
Who does it

The same team

What you get

The backend with the business logic in it, and the portal your team runs the product from.

The cloud
Who does it

The same team

What you get

AWS or Google Cloud, built as code, in your accounts, so it can be rebuilt and it's yours.

QA
Who does it

Our own QA people, in the build from the start

What you get

Testing through the build, not bolted on at the end.

Shipping to the stores
Who does it

We do it

What you get

We build the CI/CD that ships each release, and we deploy on your accounts, App Store and Google Play, in your name.

Ownership
Who does it

Done from day one, not written into a contract

What you get

The keys, the accounts, the domain and the code, in your name from the start. We have seen too many companies find out late that they don't own parts of their own product.

After launch
Who does it

We stay on it

What you get

See §05.

Capacity and continuity

Every build has a named project lead and a named senior engineer who stay on it from the first call to launch. They coordinate the rest: our own design team, who work with you directly, the engineers the build needs, and QA through it. You'll know everyone on your build by name. A second engineer stays current on the work, and it's documented and shared as we go, so one person being out doesn't stop your build. We take on a small number of builds at a time, so the people you meet are the people who ship, and if we can't start when you need us, we say so on the first call. Brian still works directly with clients. Barry sets the technical direction, reviews the engineers' work, and still writes code. Neither has to be on your build for it to be ours. Senior engineers, based in Ireland, in the EU. The same senior people from scope to delivery, no offshore hand-off. We overlap your US working morning.

§ 03 · The firmware boundary

We design the link to your device. We don't write the firmware.

If your product has a device in it, the boundary matters, and we state it before you ask. We design the communications interface between the device and the app with your embedded team: the protocol, the packets and the formats, in both directions. Then we build the app side of it: the Bluetooth Low Energy link, an SDK if other apps need one, and the path for firmware updates from the app to the device. We have done it over Bluetooth and BLE, serial cable, USB, and low-power and wireless links. What stays with you: the firmware itself, written by your embedded team or your hardware partner, to the interface we designed together. We do not design or manufacture the hardware. If you need the firmware written, say so, and we'll tell you who to talk to.

§ 04 · Named proof · The most recent connected build first.

The named work behind the claim.

Card 01 · Epona Biotech · Veterinary diagnostics · Bluetooth reader

The native iOS and Android apps that talk to their Bluetooth reader, the backend and the admin portal. Since 2018, and still active.

Card 02 · ETL · Prepaid vouchers and airtime · Bluetooth, USB and network printing

An offline-first Android POS for prepaid vouchers and airtime, printing to the shops' own printers over Bluetooth, USB and network, and over serial cable in the early years. More than 170 releases. Thirteen brands on one codebase. Our longest client relationship. Still live, still trading. Since 2014.

Card 03 · ResMed · S+ bedside sleep sensor · Bluetooth

The consumer apps on iOS and Android, the Bluetooth link to the device, and the cloud platform. ResMed's first consumer product, in the home and on the market.

Card 04 · ResMed · Sonar sleep tracking SDK · No device

Sleep tracking through the phone's own speaker and microphone, built as an SDK and shipped in SleepScore. A sensing method that did not exist before, in a product that reached market.

Card 05 · Someone Like Me · Peer-support platform

A cancer peer-support platform with moderation built in, live and in use. Purpledecks built the backend, the admin portal, the data layer and the infrastructure it runs on, and built the screens with the founder.

"I'm very much a person who needs to understand how things work, not just approve them. Brian explained things properly, every time, until it made sense to me. I felt like Brian and his team held my hand through the whole experience, and I'm delighted with the end result."

Vanessa Mooney, founder, Someone Like Me

Card 06 · Fire1 · Implantable cardiac device · Bluetooth SDK

The original Bluetooth SDK for Fire1's implantable cardiac device, now in clinical trials.

We have also built and run consumer apps at scale for RTÉ, Musgrave / Centra, Eir and Fáilte Ireland.

All case studies →
§ 05 · After launch

Launch is where a product starts.

On a new build, where the delivered system is our own work, we fix defects in that work reported within ninety days of handover. We don't make that promise on every engagement. Then we maintain what we build, we update it, and we build the next thing. Our longest client relationship began in 2014 and is still live. Epona has been with us since 2018.

A product needs more than its code to run: support, store reviews, crash monitoring, bugs, new features, maintenance, and the people inside your company who will own them. Before launch we help you put that in place, and we tell you what your product will be asked for, from a privacy policy to a security policy. We're engineers and product people, not lawyers, and where you need a lawyer we'll say so.

What it costs to keep an app running, in numbers →
§ 06 · When we're not the right fit

If price is the only thing that matters. We're not the cheapest, and we won't pretend to be.

If you want an app from a template or a no-code tool. There are cheaper ways to get one, and we'll say so.

If you need the hardware designed or the firmware written. We build the software that talks to the device, not the device.

If it's a pure AI project with no product to build. That's our sister brand, Deep Purple AI. We'll point you there.

If you need a manned helpdesk running your operations. We maintain and support what we build. We're not a 24/7 service desk.

If you need the comfort of a big name. We're a small firm, not a big brand. That's the point of us.

Straight answers

What does it cost to build an app?

We don't publish a build price, and we won't quote one without understanding the product. What drives it: how many platforms, how much logic sits in the backend, whether there's an admin portal, what it integrates with, whether there's a device, and what a store, a regulator or an investor will ask the product to show. It starts with a technical conversation, then a scoped proposal, fixed price or time and materials. We're not the cheapest, and we'll tell you early if the budget and the product don't match.

How long does it take?

Depending on size, two to five months to a first release. We'll tell you which end you're at before we quote. What moves it is the same list as cost: the platforms, how much logic sits in the backend, whether there's an admin portal, what it integrates with, and whether there's a device with a firmware team on the other side of it. It also depends on you: how quickly decisions and sign-offs come back, and whether you arrive with a brand or we start there with you.

Native or React Native?

Native when the product leans on the phone: Bluetooth, sensors, background work, performance, or the polish each store expects. React Native when the app is mostly screens over a backend and one codebase across both platforms is the better trade. We build both, and we'll say which fits before we quote.

Do you build the backend and the admin portal too?

Yes. The backend, the admin portal and the cloud are part of the product, built by the same team that builds the app.

Do you work with our firmware team?

Yes. We design the communications interface with your embedded team, then build the app side of it. We don't write the firmware, and we say so before you ask.

Who submits to the App Store and Google Play?

We do, on your accounts and in your name, with the CI/CD we build to ship each release.

What do you subcontract?

We don't subcontract product delivery. Everyone who designs, builds or tests your product is a Purpledecks employee. Where a build needs a specialist, device cybersecurity for one, we bring them in and manage them inside the same lifecycle.

What happens after launch?

We stay on it: we maintain what we build, we update it, and we build the next thing. Before launch we set you up for the parts around the code, from support to store reviews to the people who will own them.

Start here

Talk to an engineer.

It starts with a technical conversation, not a sales call. Your product, what it has to do, what sits behind it, whether there's a device, and what comes next. Then a scoped proposal that names your project lead and senior engineer, the build, the launch, and the ninety days after it.

PURPLEDECKS
53.7°N 7.8°W · IRELAND
EST. 2012 · EU
hello@purpledecks.com

Best fit is a funded founder who wants the apps and the systems behind them built as one product by a named senior team.

Working since 2012 · Senior engineers only · No offshore hand-off · References on request
Reviewed by Brian Egan, Founder and CEO · Last reviewed 30 August 2026