How much does firmware development cost?

A focused firmware project for a simple sensor device may fit a modest five-figure budget, while a connected product with BLE or Wi-Fi, OTA updates, power management, and safety requirements typically runs higher. The biggest cost drivers are wireless complexity, reliability requirements, and how mature the hardware is — firmware developed alongside the electronics is consistently cheaper than firmware forced onto a frozen board.

What is the difference between firmware and software?

Firmware is software that runs inside the device itself, on a microcontroller with kilobytes of memory, no screen, and often no operating system — and it must run for years without a reboot. Application and cloud software run on phones and servers with abundant resources. The engineering mindsets differ enough that an excellent app developer is not automatically a firmware developer.

Do I need an RTOS or is bare metal enough?

Simple devices with one main job run well on bare metal — a single loop plus interrupts. Once the product juggles concurrent tasks (radio, sensors, UI), a real-time operating system like FreeRTOS or Zephyr adds structure and reliability. Products needing rich graphics or complex networking may justify embedded Linux, at a real cost in power, boot time, and BOM.

How do over-the-air firmware updates work?

The device receives the new firmware image via its radio — directly, or relayed through a companion app — verifies its integrity and authenticity, writes it to a spare memory region, and swaps over on reboot. Two properties are mandatory: the update must survive interruption mid-transfer, and the device must roll back automatically if the new version fails to boot.

Why does my product's battery drain so fast?

In most cases the cause is firmware, not the battery: the microcontroller never entering deep sleep, radios left on between transmissions, or sensors sampled far more often than needed. Disciplined power management — sleep by default, event-driven wake-up, batched transmissions, and current measurement in every operating mode — routinely turns days of battery life into months.

What does FDA-compliant embedded software require?

Safety-relevant device software is developed under a documented lifecycle aligned with standards such as IEC 62304: verifiable requirements, tests traced to each requirement, risk analysis, and full version and change control. It adds process overhead, but it is what makes it possible to demonstrate to the FDA — and to yourself — that the device is safe.

Embedded Software Development — Firmware Development Services for Hardware Products

What Embedded Software Actually Is

Embedded software — firmware — is the code that runs inside the product itself, not on a computer or a phone. It lives on a small microcontroller inside the device, where it drives motors, reads sensors, manages the battery, and talks to the outside world. In most smart products, it is the component that decides whether the device feels reliable or feels like a toy.

The difference from ordinary software engineering is not the language — it is the environment: kilobytes of memory instead of gigabytes, no operating system or a minimal one, no screen to debug on, and code that must run for years without a reboot. A brilliant cloud engineer is not automatically a firmware developer, and knowing that distinction saves founders an expensive mis-hire.

Rule One: Firmware Is Written Alongside the Hardware

The costliest mistake in embedded projects is finishing the hardware and only then starting to write code. In practice, firmware is what exposes hardware problems: a pin that cannot be controlled, a noisy measurement channel, a wake-up time that is too slow, a peripheral that does not respond in time. When those discoveries arrive after the board design is frozen, every fix costs a full board revision.

That is why professional teams write basic bring-up firmware on the very first board revision — even if it only blinks an LED and reads one value. It is the same iterative loop that drives good electronics development: hardware and code proving each other out, revision by revision, on real prototypes.

What Embedded Software Manages in a Product

Sensor reading and signal processing. Raw measurements are almost never usable — they need filtering, calibration, and temperature compensation. The measurement quality of your product is decided here, not just in the sensor's datasheet.
Motor and actuator control. Precise timing, acceleration profiles, and detection of stalls or abnormal load.
Power management. Sleep modes, event-driven wake-up, and shutting down unused peripherals. This is what determines whether the product runs a day or a month on a battery.
Communication. Bluetooth Low Energy, Wi-Fi, or cellular — including graceful handling of disconnects, which are the normal state in the field, not the exception.
Reliability and self-recovery. A watchdog that restarts the device if code hangs, state saved in non-volatile memory, and silent recovery from faults. The user should never know something went wrong.
Field updates. The ability to fix a bug after the product has been sold — the difference between an expensive recall and an invisible over-the-air update.

Firmware Updates: A Day-One Requirement

Every hardware product ships with bugs; assuming otherwise is not professionalism, it is optimism. So an update mechanism is not an advanced feature — it is a baseline requirement, and it must be designed before the hardware is frozen. Two non-negotiable principles: the update must survive an interruption mid-transfer — a device bricked because the phone locked its screen is a design failure, not bad luck — and the device must be able to roll back automatically if the new version fails to boot. When updates are delivered through a companion app, firmware and app are one system project, not two separate ones — see our guide to companion app development.

Dividing the Work: What Lives in the Device and What Lives Outside

Decide this early, because it drives both cost and reliability. Three battle-tested rules:

Anything safety-critical lives in firmware, always. If an emergency stop depends on a connected phone, the product is not safe.
Heavy computation goes outside the device. A small microcontroller is the wrong place for complex processing; the app or the cloud backend does it better.
Frequently changing logic stays out of firmware. Updating code in the field is harder than deploying to a server.

Architecture Choices: Bare Metal, RTOS, or Embedded Linux

Simple devices run "bare metal" — a single loop with interrupts, minimal and predictable. As soon as the product juggles several jobs at once — radio traffic, sensor sampling, a user interface — a real-time operating system such as FreeRTOS or Zephyr earns its place, giving structure to concurrency without the weight of a full OS. Products that need rich displays, video, or complex networking step up to embedded Linux on an application processor — with real consequences for cost, boot time, and power. Choosing the right level, not the most powerful one, is a hallmark of experienced firmware engineering.

Choosing the Processor: A Decision That Is Hard to Undo

The microcontroller sets your product's boundaries for years, so it is never a "minor technical detail." Not the strongest — the best fit: an oversized processor adds cost, heat, and battery drain, while an undersized one forces an architecture change mid-project. And the often-forgotten factor is supply: a part with a single source and long lead times is a project risk, which is why designs should favor components with declared alternatives.

When the Product Is Medical or Safety-Critical

If the device is intended for medical use, industrial control, or any context where failure is dangerous, embedded software is written under a documented process: requirements phrased so they can be verified, tests traceable to every requirement, and full version control. For medical devices this aligns with FDA expectations and standards such as IEC 62304 — not bureaucracy, but the mechanism that lets you prove the product is safe. More on this in our guide to medical device development.

Who Writes the Code

Embedded development sits exactly on the seam between hardware and software, and it succeeds when the firmware engineer works beside the electronics engineer — not across time zones from them. Projects where hardware, firmware, and mechanical design are managed separately get stuck precisely at the interfaces. At Projects House, all these disciplines sit under one roof as part of a complete new product development process — which is why that seam never becomes the bottleneck.

The Bottom Line

Embedded software is the code inside your product, and it determines reliability, battery life, and that hard-to-fake feeling that the device "just works." The three rules that matter most: write it in parallel with the hardware, design the update mechanism from day one, and decide deliberately what lives in firmware and what lives outside it.

Turning an idea into a working device? Reach out to the Projects House team through our contact form — we develop hardware and firmware as one system, from processor selection to production handoff.

Embedded Software Development: The Code Inside Your Product