It depends on what the app has to do. A business app, an app that talks to devices and a virtual reality app need different experience, so ask to see apps like yours. Then ask who writes the code, what the first version does and what it costs, and who maintains it after launch. The five companies, and who each one suits, are below.
SEIRO, one of the five companies, wrote this guide. It doesn't cover freelance platforms or no-code tools. If you're not sure what kind of app you need, start with native, cross-platform or web, and for the budget, with how much an app costs.
The agencies
We chose these five companies with four criteria:
- They build apps for clients in Spain, with a team or offices here.
- They have apps in production and clients or cases you can check.
- They cover different needs: the business app, hardware, virtual reality and large-enterprise projects.
- Each profile is based on the company's own site: what it says about itself, with no third-party opinions.
ABAMobile
ABAMobile is a mobile app agency based in Llanera, Asturias. Its site says it builds smartwatch and wearable apps for iOS and Android, IoT solutions and projects using NFC, Bluetooth and beacons, including work for equipment makers. Named clients include Alsa, Signify, Circutor and Ragt.
A fit if: need an app that talks to devices, wearables, NFC or IoT.
Plain Concepts
Plain Concepts is a technology consultancy founded in 2006 with more than 700 employees. In Spain it has offices in Barcelona, Madrid, Bilbao, Seville and León, plus more than 26 delivery centres worldwide. It works with large companies on AI, software engineering, data, cybersecurity and cloud. Its case studies include Zara's iOS app, and its clients include Telefónica, Iberdrola, Ferrovial and Coca-Cola.
A fit if: are a large company whose project needs a consultancy with hundreds of engineers.
Rudo Apps
Rudo Apps is a mobile app agency in València with a team of 60, part of Lãberit, a Valencian IT company with more than 800 employees. It builds only apps: native in Swift and Kotlin, and cross-platform in Ionic and Flutter. Its portfolio includes Volvo, Banco Santander, BNP Paribas and Saks.
A fit if: are a large brand that wants a big dedicated app team inside an 800-plus-person IT group.
SEIRO
SEIRO is a software engineering studio based in Barcelona, made up only of senior software engineers. It has worked for clients since 2023 and was incorporated in 2025. It builds iOS and Android apps, as well as custom software, web platforms and applied AI, mainly for SMEs and startups. Its apps include iKandi, which it took over already live on iOS and then brought to Android, and Sindi, the app of a private restaurant club.
A fit if: are an SME or a startup and need an iOS and Android app, from the first version to its growth.
Virtualware
Virtualware is a 3D and extended reality (XR) software company with an office in Basauri (Bizkaia) and others in Canada, the US and Sweden. Its site says it has spent more than 20 years building 3D solutions for businesses: simulation, digital twins and immersive training, on its VIROO platform. It shows clients such as GE Vernova, Alstom, ADIF, Repsol, Iberdrola and SEAT.
A fit if: need virtual reality, 3D simulation or a digital twin to train staff or run industrial sites.
Side-by-side overview
| Agency | Type | Speciality | Who it’s for | Where |
|---|---|---|---|---|
| ABAMobile | Mobile agency | Apps for wearables, IoT, NFC and Bluetooth | Companies and equipment makers | Llanera, Asturias |
| Plain Concepts | Technology consultancy | Software projects for large companies | Large enterprises | 5 cities in Spain, plus abroad |
| Rudo Apps | Mobile agency | Apps only, native and cross-platform | Large brands | València |
| SEIRO | Software studio | Business apps for iOS and Android | SMEs and startups | Barcelona, remote |
| Virtualware | XR and 3D studio | Virtual reality, simulation and digital twins | Industry, energy and transport | Basauri (Bizkaia), plus abroad |
Already holding two or three quotes for your app? On a free 15-minute call we'll go through them with you, even if none of them is ours.
How to choose
- Start with what the app has to do. A business app, an app that talks to devices and a virtual reality app need different experience. Ask to see apps like yours.
- Ask who builds it. Who writes the code, how experienced they are, and who your day-to-day contact will be.
- Agree what the first version does. What's in, what waits and what it costs, before work starts. The market ranges are in how much an app costs.
- Ask what happens after launch. How each release is tested, who maintains the app and who owns the code.
- Check before you sign: ask to see two of their published apps, talk to their clients and ask them the seven questions for choosing an agency.
Is your app a fit for SEIRO?
If it's an iOS and Android app for an SME, a startup or a growing company, probably yes. On a free 15-minute call with a senior engineer we'll look at what the first version has to do, whether it should be native, cross-platform or web, and where to start.
And if your app needs hardware, virtual reality or a team of hundreds of engineers, we'll tell you which company on this list suits it better.
Frequently asked questions
What are the best app development companies in Spain?
There's no single best one: it depends on what the app has to do. Ask to see published apps like yours, ask who writes the code and who maintains it after launch, and talk to their clients. This guide has five companies and who each one suits.
How much does it cost to build an app in Spain in 2026?
Mostly it depends on what the first version does, whether it needs an admin panel and how many systems it connects to. The market ranges, with what each one includes, are in our guide to how much an app costs.
Does my app need to be native or cross-platform?
For most business apps, cross-platform is enough: one codebase for iOS and Android. Native pays off when the app depends heavily on the phone's hardware or on graphics performance. Our native, cross-platform or web guide explains it.
What should I ask an app company before signing?
Which of its apps are still live and in use, who writes the code and how experienced they are, who owns the code at the end, how it tests the app before each release and who maintains it after launch.
This article reflects publicly available information as of 2026. Company details may change over time.