Choose native when the app depends on device hardware, offline working or top performance, and cross-platform when you need iPhone and Android on a tighter budget and the app is mostly forms, lists and content. A web app is often enough for staff who work at a desk. ERS IT Solutions builds all three from Blanchardstown, Dublin 15, with 25+ in-house developers, and picks per project.
What are the three basic types of mobile apps?
There are native apps, cross-platform apps and web apps. A native app is written separately for each platform in its own language. A cross-platform app shares one codebase across iPhone and Android. A web app runs in the browser, and a progressive web app (PWA) can be installed to the home screen and work offline.
| Native | Cross-platform | Web app / PWA | |
|---|---|---|---|
| Codebases | One per platform | One shared | One |
| Device hardware (Bluetooth, scanners, keys) | Full access | Good, sometimes via plugins | Limited |
| Offline working | Strong | Strong | Possible, more limited |
| App Store listing | Yes | Yes | Not needed |
| Build cost for two platforms | Highest | Lower | Lowest |
iOS vs Android app development: which first?
In Ireland the split is close to even. In September 2026, Android had 52.62% and iOS 47.37% of mobile operating system use in Ireland (StatCounter). For a public-facing app that means you need both.
For an internal app the answer is different: build for the devices your staff carry. If the company issues Android tablets or rugged handhelds, build for Android. That is what ERS did for MAMA, a medication app for nursing homes run on Android tablets, and for AAA Vet Care's TB testing app, which works with physical device keys because vets on farms wear gloves.
Android and iOS app development: what is different?
The two platforms use different languages, design rules, review processes and release cycles. iOS apps are written in Swift and follow Apple's Human Interface Guidelines, are tested through TestFlight and go through App Store review. Android apps are written in Kotlin and can be published on Google Play or distributed privately to company devices. Each platform also has its own yearly update rules (see app development cost).
What is the best language for Android app development?
Kotlin. Google has said since 2019 that Android development is "increasingly Kotlin-first" and recommends starting new Android apps in Kotlin. Its modern interface toolkit, Jetpack Compose, is Kotlin-only. Java still works and is fully interoperable, which matters if you are taking over an older Android app. ERS builds native Android apps in Kotlin and iOS apps in Swift and SwiftUI.
Cross-platform mobile app development vs native
Cross-platform frameworks let one team write most of the code once. Flutter, supported by Google, describes itself as a framework for "natively compiled, multi-platform applications" from "a single codebase". React Native is "written in JavaScript, rendered with native code", so its screens use the platform's own interface components.
When cross-platform makes sense
- Customer apps that are mostly content, forms, accounts and notifications.
- A first release or MVP where you need both stores without paying twice.
- Teams that will maintain one codebase rather than two.
When native is the safer choice
- The app depends on hardware: Bluetooth sensors, barcode scanners, physical keys or the camera.
- It must work all day with no signal and sync later, like the apps ERS built for farms and wards.
- Performance and battery life matter, or you need new platform features on day one.
Even with cross-platform you still need some native work, separate App Store and Google Play submissions, and testing on real devices for both.
Which should an Irish business choose for field staff?
For field staff, native usually wins, because field apps live or die on offline working, hardware and battery. ERS's Android page puts it plainly: we build apps "to cope with poor connectivity, busy days and tough environments". Cross-platform is worth it when the field app is simple forms with good signal and staff use a mix of iPhone and Android.
The APHA Compendium app is a good middle case. ERS rebuilt it for iOS and Android, and it works fully offline after its first sync because vets use it on rural farms.
App vs web development: do you need an app at all?
Often you don't. If users are at a desk, or only need the system now and then, a well-built web application is cheaper to build and update, and there is no store review. Google describes PWAs as web apps that can be installed into their own window and that users expect to load even on slow connections or offline.
Build an app when users need it every day on the move, need offline working or device features, or expect to find you in the App Store. ERS built Premier Lotteries Ireland a retailer portal and mobile web app with iOS and Android push notifications, which shows the line between web and app is not always either/or.
What about web app development in Ireland?
A web app is a custom application that runs in the browser: a client portal, a booking system, a case management tool. ERS builds these as part of custom application development, for example the JMB vetting portal for schools.
A short guide to Android app development
- Discovery. Who uses it, on which devices, with what signal, connected to which systems.
- Wireframes and prototype. Agree the key screens before code.
- Build in Kotlin, with the back end and integrations alongside.
- Test on real devices, including offline and low-signal conditions.
- Launch through Google Play or private distribution to company devices.
- Evolve. Keep up with Google's yearly target API rules and add features from real use.
The same steps apply to iOS, with Swift, TestFlight and App Store review in place of Kotlin and Google Play. See Android app development and iOS app development.