Expertise / Applications
Cross-platform app development services for connected products
One code, multiple platforms. Indeema designs, builds, integrates, tests and supports cross-platform apps for iOS and Android, and engineers them as part of connected products: the app works with a device, its firmware and a cloud back end, and native code is used where the shared layer stops.
What it means
What is cross-platform app development?
Cross-platform development is an approach in which the same codebase is used to build an application for several platforms, most often iOS and Android, and with some frameworks also web and desktop. Instead of writing and maintaining two separate native apps, one team writes the user interface, state, business logic and networking once, and adds platform-specific code only where a feature needs it.
In a connected product, that platform-specific part is usually where the app meets the device: Bluetooth stacks, background execution, notifications, permissions and sensor access behave differently on each operating system. Deciding early what stays shared and what becomes a native module is what makes a cross-platform app work as well as a native one for its job.
Services
Our cross-platform app development services
From the first architecture review to support after launch. Engage us for one of these or for the whole lifecycle.
Cross-platform application consulting and architecture review
Whether it is an existing product or a new idea, we review the requirements and the architecture to prevent risks and manage challenges early, and design a single application architecture for all target platforms: which framework fits, what stays shared, which features need native modules, and how the app talks to the device and the cloud.
Custom cross-platform application development
We build the shared application layer and the native modules it depends on, so the app behaves the way people expect on each platform and reaches iOS and Android users from one codebase and one release cycle.
Cross-platform application design
UX and UI design for cross-platform apps: one product language that still respects iOS and Android conventions for navigation, controls and permission prompts, with screens that show device state and connection quality clearly.
UI/UX design for connected systemsCross-platform application integration
Integration needs vary with the stage. At the idea stage we define which third-party services the product needs and select a tech stack that integrates them. In later stages we check which services, SDKs and plugins are compatible with the framework and language already in use, and write native bridges where they are not. In a connected product, integration also covers the device link and the cloud APIs.
Cross-platform application testing
Testing is a significant part of any development process. We test shared logic once and platform behavior on every target: functional, integration and regression testing on real phones and, in a connected product, with the real device, firmware version and network conditions.
Cross-platform application support
Post-delivery work keeps the app aligned with business needs and the market as it evolves: operating-system releases, framework upgrades, store policy changes and new device firmware all need compatibility testing, updates and new features over time.
Maintenance and product support
When it fits
When is a cross-platform app the right choice?
Choose cross-platform when
- You want to save time: the same features and user flows ship on iOS and Android together, from one codebase.
- You want to cut down on duplicated engineering: one team and one test suite for shared logic, instead of two apps to build and keep in step.
- Most of the app is screens, state, data and networking, and device-specific code is limited enough to live in native modules.
- You need to launch on both platforms at once, for example a companion app or an MVP.
Consider native when
- The core of the product depends on platform features that must be used the day a new OS version ships, such as widgets, watch apps or advanced background modes.
- Graphics, video, audio or real-time processing is so demanding that every frame or millisecond counts.
- The product targets only one platform.
- Most of the code would end up in native modules anyway.
Cross-platform vs native
How the two approaches differ
| Aspect | Cross-platform | Native |
|---|---|---|
| Codebase | One shared codebase, plus native modules where needed | Separate iOS and Android codebases |
| Feature parity | Both platforms get the same release by default | Each platform is built and kept in step separately |
| Device and OS features | Through plugins or custom native modules; brand-new OS APIs may need a bridge first | Direct access to every platform API as soon as it ships |
| User interface | One design adapted to platform conventions | Platform UI components throughout |
| Performance | Suits most monitoring, control and business apps; profile heavy graphics or real-time work early | The most headroom for graphics-, media- or latency-critical work |
| Team and maintenance | One team and one test suite for shared logic; framework upgrades are an extra dependency | Two specialised codebases; no framework layer to upgrade |
Multi-platform does not always mean one codebase. For a drill app used outdoors and in motion, Indeema built native iOS and Android apps and later modernized them to SwiftUI and Jetpack Compose. Mobile and web apps for learning marching-band drill on the field
Platform-specific detail lives on the native pages: iOS app development and Android app development.
Technologies
Cross-platform frameworks and technologies
The choice of stack depends on the business goals, the existing code and team, and the performance the product needs. We recommend a framework after the architecture review, not before it.
Flutter
DartOne codebase compiled to native code for iOS and Android, with its own rendering engine for a consistent interface. Used in Indeema projects for device apps with Bluetooth connection, over-the-air firmware updates and notifications.
In practice: Adding Bluetooth setup and OTA updates to an indoor plant-care control app · Building an indoor air monitor and companion app across two device generations
Qt and QML
C++A C++ framework with a declarative UI language, a good fit when the product or team already works in C++. Used in an Indeema project for an iOS and Android air-quality monitoring app.
In practice: Indoor environment monitor with device, cloud and mobile app
React Native
JavaScript / TypeScriptPlatform UI components driven from JavaScript or TypeScript. Worth assessing when web and mobile teams share a JavaScript stack.
.NET MAUI
C#Microsoft’s successor to Xamarin, which reached end of support in May 2024. Relevant for teams with .NET skills, and the usual migration path for an existing Xamarin app.
Native modules
Swift / KotlinPlatform code for Bluetooth, background work and other features the shared layer does not cover, written in each platform’s own language.
Architecture and integration
Five decisions that shape a connected cross-platform app
Start from the device, not the framework
List what the app must do with the product: pair over Bluetooth Low Energy or Wi-Fi, stream telemetry, run background tasks, receive push messages, update firmware. Each requirement decides how much platform-specific code the shared layer can carry.
Draw the shared and native boundary
Business logic, state and networking usually share well across platforms. Bluetooth stacks, background execution, notifications, permissions and camera or sensor access differ by operating system. Name which parts stay shared and which get a native module, so the choice is a design decision.
Connect to the cloud and third-party services
Agree the API contract with the back end early: authentication, real-time data, history and remote commands. Check every SDK and plugin the app needs against the framework version, and plan a native bridge where one is missing.
Plan for background and offline behavior
A connected-product app is often used when connectivity is weak or the device is out of range. Decide what the app caches, how it reconciles state with the device and the cloud after reconnection, and what the user sees while it waits.
Update the device from the app
When the app starts firmware updates over Bluetooth, the update flow, recovery after an interrupted transfer and version compatibility belong to one contract between the app and the firmware.
Connected products
Where cross-platform apps fit in a connected product
In a connected product the app is one layer of a single system. It is designed together with the device protocol and the cloud API, so the same team can answer what happens when the connection drops or the firmware changes.
Consumer IoT companion apps
Apps that set up a device, show its readings and send alerts, on whichever phone the customer owns.
Industrial and field apps
Apps that installers and operators use to connect to controllers on site, configure them and update their firmware.
Monitoring and alerting apps
Current and historical readings, thresholds and notifications from sensors and connected equipment.
Business and admin apps
Companion tools for the business that runs the product: accounts, devices, roles and settings.
The rest of the stack
- Applications & Experience The whole application layer of a connected product: mobile, web and design.
- Embedded & Firmware The device side of the app-to-device contract.
- Cloud & Connected Systems The services and APIs the app talks to.
- IoT Product Engineering Device, cloud and applications as one scope.
Testing, performance and quality
How we keep one codebase reliable on every platform
Test on the hardware you will ship with
Emulators rarely reproduce radio behavior, power management or vendor-specific operating-system changes. Define the device, phone and operating-system matrix and the pass criteria for pairing, reconnection and update flows before build starts.
Measure performance where people feel it
Profile start-up time, scrolling, data-heavy screens and connection time on lower-end phones as well as flagships, and move a hot path into native code only when measurements show it is needed.
Run a beta before a broad release
A release to a small group of real users, across device models and operating-system versions, finds the problems that test plans miss.
Decide the release and maintenance path
Store review, operating-system releases and library updates keep arriving after launch. Agree how updates are tested against the device firmware and who owns compatibility over time.
Why Indeema
Why teams choose Indeema for cross-platform development
One team from the device to the app
The same engineering organisation works on firmware, cloud and applications, so the app is designed against the real device and back end.
The framework follows the product
A wide range of technologies, chosen to fit the product’s needs and requirements rather than a house default.
In-house experts
The engineers who design, build and test your app are Indeema’s own team.
Transparent, iterative cooperation
Work is planned in short iterations, and trade-offs such as what stays shared and what goes native are agreed with you openly.
Case studies
Cross-platform apps Indeema has engineered
Three connected products where one codebase serves iOS and Android. Client names and figures are not shown.
- FlutterIrrigation and lighting control app
An existing Flutter MVP app was upgraded and extended with Bluetooth connection and control, over-the-air firmware updates over Bluetooth, device configuration, activity logs and notifications, with an admin interface for the business owner.
Adding Bluetooth setup and OTA updates to an indoor plant-care control app - FlutterIndoor air monitoring system
Flutter gave the client one app codebase for Android and iOS. The app shows current and historical readings and sends notifications, and was updated with new sensor readings for the second device generation.
Building an indoor air monitor and companion app across two device generations - QtAir-quality monitor with cloud platform and app
The team chose the cross-platform Qt framework so one codebase serves iOS and Android, and tested the app end to end with the device and cloud before a beta release to a small user group.
Indoor environment monitor with device, cloud and mobile app
Related engineering insights
- Home automation app development roadmap Platform and codebase choice for a smart-home app, including where Bluetooth or Thread work needs native code.
- How to create an IoT app The wider IoT app process: architecture, connectivity, security and cross-platform development.
FAQ
Cross-platform app development questions
How do you define cross-platform mobile application development?
It is the way of creating one app, from one shared codebase, for several platforms, usually iOS and Android. It is a strong option when time and budget matter and both platforms need the same features; native code is still added for the parts that depend on a specific operating system.
What technologies are involved in cross-platform app development?
The main frameworks are Flutter (Dart), React Native (JavaScript or TypeScript), Qt (C++) and .NET MAUI (C#), which replaced Xamarin after Xamarin reached end of support in May 2024. Native modules are written in Swift or Kotlin. The choice of tech stack depends on the business goals and the performance you need; Indeema’s documented projects use Flutter and Qt.
Why should you choose a cross-platform app for your business?
In simple words, it is one code for several platforms. It is the better choice if you want to save time, cut down on duplicated engineering and keep iOS and Android in step. If the product depends on deep platform features or extreme performance, native development is usually the better call.
What does cross-platform integration consulting cover?
An architecture review of how the app will connect to everything around it: which framework and plugins fit, which third-party services and SDKs are compatible, where native bridges are needed, and how the app talks to the device and the cloud. It works for a new idea and for an existing app that is hard to extend.
Is a cross-platform app slower than a native one?
For most monitoring, control and business apps the difference is not noticeable when the app is built well. It matters for heavy graphics, video or real-time processing. We profile on real phones and move only measured hot paths into native code.
Can a cross-platform app connect to a Bluetooth device and update its firmware?
Yes. The Bluetooth connection is usually handled through a plugin or a native module per platform, and the update flow is designed together with the firmware. Indeema has delivered a Flutter app with Bluetooth control and over-the-air firmware updates.
Can you take over or modernize an existing cross-platform app?
Yes. We start with a review of the code, the framework version and the plugins, then upgrade, refactor or extend it. If an app is built on a framework that is no longer supported, such as Xamarin, the review covers the migration options.
Can the same codebase also run on the web or desktop?
Flutter, Qt and .NET MAUI can also target desktop, and Flutter can target the web, but a product used mainly in a browser is often better served by a dedicated web application. We decide per surface during the architecture review.
Tell us about your project
Start with what the app must do with the product
A first conversation is about the device, the platforms and the trade-offs, not a framework pitch.
Bring us
- The device, or the plan for it
- The platforms and the people who will use the app
- Any existing app, codebase or framework
- The part you want Indeema to own
Related services
- iOS app development When Apple platform rules shape the design.
- Android app development When device diversity drives the design.
- MVP development When both platforms need to launch quickly to test the product.
- Web platforms and dashboards When the product is used mainly in a browser.