Designing IoT Devices that Work

Many IoT projects fail. And there are many reasons for failure. Connectivity is a major one.

In many ways, cellular connectivity is great for IoT – secure, reliable, widespread coverage. But in other ways, it’s not.

Mobile networks are designed for people and phones, not IoT. Mobile network operators operate in siloed geographies, governed by local regulators. With little interoperability between operators and constant change in the telecom landscape, it’s difficult for IoT deployments to operate smoothly.

We have overcome these obstacles to offer global, ubiquitous connectivity for IoT devices, but even our sophisticated AnyNet+ eSIM and Connectivity Management Platform can’t connect devices that aren’t designed properly for cellular connectivity. Device design is absolutely key and connectivity must be factored in from the start.

Moreover, it goes beyond connectivity. IoT devices may need to withstand extreme temperatures and wild weather, operate in remote or inaccessible areas, or last for a decade on a non-rechargeable battery.

IoT device prototyping

Aldolex logo
“Eseye’s rapid prototyping methodology approach is cutting our time to market by about 50%, which, in a fast-moving industry, is very important”. Declan O’Brien, Director, Aldolex

Developing a working prototype is critical to IoT success. But this can take significant time – often 12-18 months. Many businesses fear their competitors will get to market first. And with no guarantee of a well-functioning device at the end, some are reluctant to invest in the process.

Designing IoT devices is hard. Finding an expert who understands the hardware and connectivity requirements can be the difference between an IoT project that succeeds and one that fails.

Here at Eseye, my team of engineers use our streamlined approach to fast-track a concept idea to a field-deployable working prototype in just 90 days.

The devices we design reach maturity (at least 1000 connections) in half the time achieved by most customers who design their own hardware.

What goes into IoT device design?

Understanding all the requirements and constraints is vital. We outline some key considerations below.

The IoT goal

Device design starts with understanding the goal of your IoT initiative. This goal drives the functionality and design of the device.

Data and processing

  • What data does your core application need from the devices?
    This determines the sensors and interfaces that your device needs to support.
  • What must your device do with the data?
    Processing can range from machine learning at the edge to a simple data forwarding mechanism.

Physical requirements

  • Are there size constraints?
    A pacemaker must be tiny, a machine-operating device may need to house a sizeable motor.
  • Do the devices have to be battery-powered?
    If the batteries are not rechargeable or replaceable, the batteries must last for the device lifetime.
  • Fixed or mobile?
    Moving devices need to handle lost connections and changing coverage areas.

The environment

  • What are the conditions like?
    Devices need protection from anything that might cause failures, such as foreign objects, dust, and moisture. Every component must be able to operate within the required temperature range.
  • What’s the terrain like?
    Connectivity in rural, remote, or inaccessible areas is challenging. Obstacles can block the line of sight to a cell tower. Even changing seasons can impact connectivity.

Regions and markets

  • Where will the device be deployed?
    What networks and roaming options are available to the devices?
  • What certification is required?
    Does it meet country, industry, and network operator standards?

Scalability and security

  • What is the security risk?
    Cybersecurity is a key challenge in IoT. A secure by design approach is needed, with risk assessments and threat modelling to ensure your data and network are protected.
  • How many devices will you be deploying?
    As you deploy more devices, the ability to manage your IoT estate remotely can help control costs. By planning ahead, you can design devices with over-the-air software updates and management capability.


  • How frequently does the device need to connect?
    What are the performance, bandwidth, and latency requirements?
  • Are Low Power Wide Area (LPWA) networks required?
    Do you need power-saving options?
  • Do you need remote network switching?
    Have you considered using an IoT SIM with multi-IMSI and eUICC capabilities?
  • How will the connectivity be managed?
    How will you detect when a connection is lost? Will battery-powered devices connect for long enough to receive commands and data?

The Eseye IoT device design service

The Eseye service combines our in-depth hardware design skills and extensive connectivity expertise.

How it works

Our service has four components:
Eseye IoT Devices Design Service Flow


During this phase, we work with your stakeholders and specialists to understand and develop your business concept.
Our agile delivery methodology iterates through design, development, and testing. This delivers key benefits:

  • With working prototypes, you can use real data to develop your applications and analytics. Together, we can use your findings to refine the device functionality and identify the data that’s essential for success. We modify the prototype design to incorporate changes – like adding or removing sensors.
  • By using prototypes in the field, we identify and resolve technical issues that might endanger a live project if undiscovered. We test device connectivity and functionality, such as over-the-air updates.
  • We can advise on strategies for manufacturing and certification. For example, the benefits of developing single SKU products or variants for different regions.
  • As we reach a level of stability in the design, you can use the prototype to raise finance and drive forward your IoT innovation.


At the end of the agile prototyping phase, you have a device design that you can take forward with confidence for development, field trials and testing.

Our service provides:

  • Full documentation of the prototype journey, showing the findings and decisions made
  • A detailed design specification and layout for your device to enable you to move forward into development and field trials

Design services to meet your needs

We offer two versions of our device design service:

Eseye - IoT Device Prototyping Service RAPIER service

Fast-track your IoT product from concept to a working prototype in just 90 days with our modular HERA300 IoT device and RAPIER approach.

Bespoke service

We offer a bespoke service for more complex projects, for example, if you need specific components or advanced processing in your device.

If you have existing designs or devices, we offer a design review service. We offer advice on resolving issues or making improvements to enable your device to better meet the requirements of your IoT initiative.

Benefits of the Eseye device design service

Our designs are built on IoT best practices:

  • Protocols, including communications, data transmission, device management, telemetry
  • Security, including data encryption, managing updates, storage of sensitive security parameters
  • Hardware design, including battery optimisation, antenna selection, environmental constraints

The AnyNet solution gives zero-touch secure global connectivity, seamless integration to the cloud, and real-time automated monitoring and control.

IoT Devices that work

Eseye IoT Device Design Service

The AnyNet solution gives zero-touch secure global connectivity, seamless integration to the cloud, and real-time automated monitoring and control.

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Jon Darley Director of Things

Jon is an IoT hardware expert with over thirty years of engineering experience. He is the driving force behind Eseye’s rapid prototyping approach, helping customers to reduce their time to market by 75% with a robust testing process.

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