UI design for embedded devices with limited resources

A case study of three demo UIs for different embedded devices: a smart thermostat, an ECG, and a smartwatch. Here are some highlights of what I learned while working on these projects.

A project for:

The most popular open-source embedded graphics library globally used by major semiconductor companies and device manufacturers across millions of deployed products.

Together We created 3 demos for 3 different customers

Smart-Thermostat for Renesas

Japanese semiconductor manufacturer ranked 16th worldwide with $9.6B revenue.

Electrocardiogram Monitor for Toradex

Swiss embedded computing specialist with $65M annual revenue.

Smart-Watch for Viewe

Chinese display manufacturer with 10+ years of producing touchscreens and smart displays.

EACH DEMO WAS IMPLEMENTED IN 3 different CHIP-BOARDS

Renesas RA8D1-EK

Toradex Verdin AM62

ESP32 S3 Touch Knob

Despite different devices and hardware, all three demos uncovered the same fundamental UX gap.

A Broad Problem

Lack of UX Thinking Makes Users Overthink

Ever struggled with a thermostat interface? That confusion reflects a curious usability gap between smartphones and embedded systems.

Most embedded devices still fail at basics.
This might stem from a historical transition: when digital screens arrived, many designers trained on static physical interfaces ( one button, one function ), faced unfamiliar dynamic states, shifting contexts, and hidden menus.

LVGL's solution

Between smartphones and physical devices

LVGL was created, in part, to help bridge that technological gap.
Why shouldn’t embedded devices be just as usable and visually appealing as smartphones or PCs? By bringing smartphone-like interfaces into the embedded world, LVGL taps into decades of UX research and design practice.

In doing so, it builds on work that began in the 1990s, when mobile phones first introduced digital screens and designers started rethinking how people interact with compact, screen-based devices.

DISCLAIMER: This is a personal interpretation.

Gábor Kiss-Vámosi, LVGL's CEO in Embedded World 2025 – Nürnberg
(Presenting my ECG demo)

Today's Business Goals

Market Positioning Through Technical Proof

Companies needed concrete evidence their hardware could deliver professional interfaces. LVGL required industry validation across medical, consumer, and IoT sectors. Toradex needed convincing demos for their healthcare customers. Renesas wanted trade show demonstrations of microcontroller capabilities.

Each demo served as strategic ammunition in embedded systems competition; proving technology readiness through working examples rather than marketing promises.