Giving Mobile App Development for Embedded Devices a Head Start

VEHMI.Mobile

Overview

VEHMI.Mobile is our foundation for developing professional mobile apps for embedded devices that act as the human–machine interface (HMI) of a product. Built with Flutter, these mobile apps run on smartphones and tablets and communicate with embedded products via Bluetooth Low Energy (BLE) or WiFi.

VEHMI.Mobile is ideal for products based on resource-constrained microcontrollers that either have no display at all or only a simple built-in HMI for basic user interaction due to cost or performance limitations.

At the same time, it works seamlessly as a mobile companion app for embedded systems with state-of-the-art integrated HMIs based on VEHMI.SBC or VEHMI.IPC.

Internet Connectivity via Mobile App

In many embedded products, permanent internet connectivity is either undesirable or not feasible due to cost, power consumption, or security constraints. VEHMI.Mobile addresses this by using the mobile app as a secure and flexible gateway between the embedded device and the internet.

Through its connection via BLE or WiFi, the mobile app can relay data and services between the device and cloud-based systems. This includes tasks such as checking for and downloading firmware updates, transmitting diagnostic or usage data, performing remote configuration, or enabling maintenance and service workflows — all without requiring the embedded device itself to be directly connected to the internet.

This approach significantly reduces system complexity and attack surface while still enabling modern, connected product features. It also allows connectivity to be added to existing embedded products with minimal changes to the device firmware, making VEHMI.Mobile a powerful option for both new developments and retrofitting established products.

Reference Implementation for ESP32

VEHMI.Mobile includes a proven reference implementation for ESP32 microcontrollers that provides transparent communication via Bluetooth Low Energy (BLE) and WiFi. It is designed to integrate smoothly with both new developments and existing embedded systems.

On the device side, the ESP32 handles secure pairing, connection management, and data exchange with the mobile app. The communication layer abstracts BLE and WiFi behind a unified interface, allowing the embedded application to exchange data without dealing with protocol-specific details. This significantly reduces integration effort and lowers the risk of introducing communication-related issues.

Depending on the overall system design and performance requirements, the ESP32 can take on different roles within the product architecture. It can either host the complete microcontroller application itself — combining application logic and communication in a single component — or act purely as a communication interface that connects an existing microcontroller-based system to the mobile app. This makes it possible to add mobile app support to legacy products without redesigning the core firmware.

While the ESP32 serves as the primary reference platform, the VEHMI.Mobile communication architecture is not limited to a single chip family. The reference implementation can be adapted to other BLE- and WiFi-capable modules or SoCs, allowing existing hardware platforms to be reused or alternative components to be selected based on cost, availability, or certification requirements.

By providing a robust, well-structured communication layer and clear integration options, VEHMI.Mobile offers a reliable foundation for adding mobile app connectivity to embedded devices — without overcomplicating the embedded software architecture.

Typical Use Cases & Industries

VEHMI.Mobile is designed for a wide range of industries where mobile apps for embedded devices are required as their primary or complementary human–machine interface. It is particularly well suited for devices where cost, power consumption, or form factor constraints limit the use of rich built-in displays.

Industrial Devices and Machinery

Many industrial products rely on microcontroller-based electronics with limited local user interfaces. VEHMI.Mobile allows to create mobile apps for configuration, operation, diagnostics, and lifecycle management of embedded devices, without adding expensive display hardware to the product itself.

Typical use cases include:

Commissioning and setup tools for machines and industrial equipment
Parameter configuration and calibration interfaces
Service and maintenance apps for technicians
Diagnostics and log data access during operation or servicing

Metering and Measurement Devices

Metering devices often prioritize low power consumption and long-term reliability, leaving little room for sophisticated onboard user interfaces. VEHMI.Mobile enables modern mobile apps to serve as the main HMI for these products.

Typical applications include:

Energy, water, gas, and heat meters
Environmental and air-quality sensors
Data loggers and monitoring devices
Portable measurement instruments

Smart Devices and Connected Products

For connected devices that interact with users only occasionally, a mobile app is often the most practical and user-friendly interface. VEHMI.Mobile provides the foundation for building reliable mobile apps that communicate securely with embedded products via BLE or WiFi.

Typical examples include:

Smart appliances and smart home components
IoT-enabled devices without displays
Consumer electronics with companion apps
Connected control units and gateways

Medical and Laboratory Equipment

In regulated environments, embedded devices often use minimal on-device interfaces to reduce complexity and validation effort. VEHMI.Mobile supports the development of mobile apps that provide advanced workflows, configuration, and data visualization while keeping the embedded device itself simple.

Typical use cases include:

Medical measurement devices
Laboratory instruments
Portable diagnostic equipment
Calibration and service tools

Systems with Existing Embedded Firmware

VEHMI.Mobile is particularly attractive for products with existing embedded firmware that need to be extended with mobile app support. By using the ESP32 reference implementation as a communication gateway, mobile app connectivity can be added without rewriting the core firmware.

This makes VEHMI.Mobile a strong option for:

Legacy products requiring modernization
Product families that need a unified mobile app strategy
Devices transitioning from local HMIs to app-based operation

Why Flutter for Companion Apps for Embedded Devices?

Developing a mobile app for an embedded product is fundamentally different from building a typical consumer app. VEHMI.Mobile is based on Flutter because it combines the strengths required for professional companion apps with the flexibility needed in embedded system environments.

Flutter vs. Native iOS and Android Development

Building separate native apps for iOS and Android quickly increases development effort, costs, and long-term maintenance overhead. Each platform requires its own codebase, development team expertise, and testing strategy — even though the user experience and functionality are largely identical.

Flutter avoids this fragmentation by enabling a single codebase for both platforms while still delivering native performance and a polished user experience. This allows UI concepts, workflows, and interaction logic to be developed once and reused across platforms.

For companion apps that evolve together with the embedded product, Flutter’s rapid prototyping and iteration capabilities are particularly valuable. Features like hot reload allow new screens, workflows, and device interactions to be tested within seconds, dramatically accelerating development and shortening feedback cycles.

Flutter vs. Web-Based Solutions

Web technologies are often considered for cross-platform apps, but they quickly reach their limits when tight integration with embedded devices is required. Reliable Bluetooth Low Energy (BLE) communication, background operation, device discovery, and low-latency data exchange are difficult to implement consistently with web frameworks — especially across iOS and Android.

Flutter provides direct access to native platform APIs and communication stacks, making it a far better fit for mobile apps that need stable BLE or WiFi connections to embedded devices. This results in more predictable behavior, better performance, and a more robust user experience — all of which are critical for professional embedded products.

Companion Apps Require Embedded Software Expertise

A companion app for an embedded device is not just another mobile app. It is an extension of the embedded system itself. It must understand device states, firmware versions, communication timing, error conditions, and update procedures — and handle all of this reliably over often unstable wireless connections.

This is where embedded software expertise becomes essential. VEHMI.Mobile builds on our deep experience in embedded systems, microcontroller firmware, real-time behavior, and communication protocols. This know-how directly influences the app architecture, data models, and interaction patterns.

It is therefore a significant advantage when the mobile companion app and the embedded firmware are designed together — not as isolated components — reducing integration risks and ensuring predictable system behavior across all operating conditions.

How Can You Profit from VEHMI.Mobile?

We use VEHMI.Mobile as a foundation for delivering professional embedded software and mobile app development services. Based on proven reference architectures and reusable software components, we support customers throughout the development of mobile HMIs for embedded products — either as the main development partner or as part of a mixed team.

Our services around VEHMI.Mobile typically include:

UX and UI design for mobile HMIs
Designing intuitive, task-oriented user interfaces tailored to the workflows of embedded devices, service technicians, and end users.
Flutter-based mobile app development
Implementing high-quality mobile apps for iOS and Android from a single codebase, optimized for companion app scenarios and long-term maintainability.
Integration with embedded firmware and communication stacks
Coordinating mobile app development with embedded firmware, data models, and communication protocols to ensure reliable system behavior, and optionally taking responsibility for the related embedded firmware development tasks.
ESP32-based connectivity solutions
Designing and integrating BLE and WiFi communication based on ESP32 reference implementations, including secure pairing and robust data exchange.
Adapting the communication reference architecture
Adapting the ESP32-based VEHMI reference architecture to your microcontroller platform, such as nRF52, Cypress PSoC, or other BLE- and WiFi-capable devices.
Collaboration in mixed development teams
Working closely with customer engineers, sharing knowledge and responsibilities, and integrating smoothly into existing development processes.

By combining embedded systems expertise with modern mobile app development, we help customers bring connected products to market faster, with lower risk and a consistent user experience.

Leverage the power of Flutter for your embedded application