Fintech
Payments, market data and market surveillance.
- Surveillance platform: 20+ data sources, 20–80 events per second
- Stripe, PayPal, Skrill, Wise and EveryPay integrations
Java 21 · Kotlin · Spring Boot · Kafka · ClickHouse
Fintech pageBackend, AI and mobile engineering for fintech, healthtech and B2B SaaS
We also build the devices
GPO-Tech is a software engineering company in Tallinn. Six senior engineers, working together since 2018. We start with a one-week AI sprint or a dedicated squad, and we show our work in cases you can check.
Four fields where we have shipped work
Each page shows the cases, the technology used in them and the people who did the work.
Healthtech
Patient apps, doctor systems and device firmware.
- PulseV: device, app and doctor CRM, 100+ users
- Two native apps for an ECG watch
Kotlin Multiplatform · SwiftUI · BLE · ESP32
Healthtech pageAI & SaaS products
Voice agents, LLM automation and SaaS backends.
- Modern Voice: production in two months, 400+ users
- AI in a CRM and in email for Welcome and UGOSKATE
OpenAI Realtime · ElevenLabs · Spring Boot · n8n
AI & SaaS pageIoT & energy
Electronics, firmware, cloud and apps.
- GPO Home: about 900 devices, 300+ customers
- Uniot: 40 street lights, 20–40 % energy saving
ESP32 · LoRaWAN · MQTT · OTA · Nord Pool
IoT & energy pageHow to start
Three ways in, each with a fixed scope and a fixed price. Pick the one that matches how far along you are.
Free 30-minute technical call
No cost
Talk your idea, current setup or technical problem through with an engineer. You leave with a concrete next step, whether or not you work with us.
Book a technical consultationAI prototype sprint
€2,000
One engineer, one week, a working MVP you can use in your business.
Start a sprintDedicated squad
from €10,000/month
2–3 senior engineers on your product, European hours, 50 % upfront.
Discuss a squadFrom physical devices to complete digital ecosystems
GPO-Tech combines electronics, embedded software, cloud engineering, mobile development and AI integrations to help companies launch reliable connected products. We can support your team from early technical discovery to prototype, development, testing and long-term support.
- 14products built from scratch
- 26+projects
- 2018team together since
- 4apps in App Store and Google Play
- EE · UA · KZ · DE · USclient countries
We also build systems for drone data: collection, fast analysis, autonomy software and image recognition. That work lives on drones.gpo-tech.com.
Work we can show
See how we help companies connect devices, build software platforms, automate operations and turn technical challenges into working systems.
Modern Voice: voice AI sales training, live in two months
- Challenge
- The founders wanted agents to practise calls with AI buyers that answer by voice. There was no product yet.
- Solution
- A Spring Boot bridge between OpenAI Realtime and ElevenLabs, scoring after each call, Stripe billing and AWS.
- Technologies
- OpenAI Realtime, Whisper, ElevenLabs, Spring Boot, Angular, Stripe, AWS
- Result
- Launched on 1 July 2025; 100+ agencies and 400+ users.
GPO Home: remote heating control from board to app
- Challenge
- Heaters with no remote control and no way to follow electricity prices.
- Solution
- Our ESP32 controller board with OTA updates, a cloud platform, a vendor dashboard and a Kotlin Multiplatform app.
- Technologies
- ESP32, BLE/Wi-Fi, NFC, Kotlin Multiplatform, SwiftUI, Nord Pool prices
- Result
- About 900 devices and 300+ customers on the platform; apps in the App Store and Google Play.
PulseV: therapy device, patient app and doctor CRM
- Challenge
- The client had therapy tables and no software.
- Solution
- A patient app on Kotlin Multiplatform that controls the device over BLE, a doctor CRM, a backend and ESP32 firmware with OTA updates.
- Technologies
- Kotlin Multiplatform, BLE, Angular, Kotlin, ESP32
- Result
- First stage in 15 days, doctor CRM in a week; 100+ users.
All case studies: fintech, AI, healthtech and IoT
Have a similar technical challenge?
Discuss similar projectServices behind the four fields
The same six services appear in every field. Pick the one your project needs, or start from the field page.
AI Integrations
LLM agents with tool calling, voice agents and AI inside your CRM and email, with a person in the loop.
Learn more
Backend & Payments
Java and Kotlin backends, event pipelines, Stripe, PayPal, Wise, EveryPay and crypto flows.
Learn more
Mobile Apps
iOS and Android apps on Kotlin Multiplatform and SwiftUI, with BLE, subscriptions and store release.
Learn more
Dedicated Team
Three to seven engineers working only on your product, from €10,000 per month.
Learn more
IoT Development
Connect devices to the cloud, collect data, build dashboards and remote control.
Learn more
Electronics & Firmware
Boards, prototypes and firmware for ESP32 and STM, with OTA updates.
Learn more
Full-cycle development from idea to launch
We can join your project at different stages: from early discovery and prototype to electronics, firmware, cloud platform, mobile app, testing, launch and support.
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01
Discovery
We analyze the task, business goal, limitations and technical risks.
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02
Architecture
We plan the solution structure: hardware, firmware, cloud, app, data flow and integrations.
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03
Prototype
We help validate the idea before full development starts.
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04
Electronics
We work with PCB, components, sensors and hardware architecture.
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05
Firmware
We develop device logic, communication, OTA updates, debugging and testing.
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06
Cloud
We build backend, APIs, dashboards, alerts and device management.
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07
Dashboard
We create interfaces for monitoring, analytics and real-time data visualization.
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08
Mobile App
We develop apps for onboarding, remote control, notifications and data visualization.
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09
Testing & Launch
We check system stability and help bring the product into production.
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10
Support
We support, improve and scale the product after launch.
Our Blog
Useful articles from our experts about technology and development
Fintech
What Actually Decides Whether Your Payments Product Ships
How to build a money transfer product when the app is the easy part — licence versus BaaS partner, corridors as commercial commitments, unit economics per transfer, and why compliance never stops costing.
August 17, 2026
GPO-Tech
Fintech
Who Owns What: Responsibility in a Growing Engineering Team
Code ownership in an engineering team that has outgrown "everyone knows everything" — named owners, written decision rights, you-build-it-you-run-it, runbooks, ADRs, handover and money-incident protocol.
August 17, 2026
GPO-Tech
Fintech
When to Hire Engineers, and Who to Hire First
When to hire engineers in a startup: hire when the bottleneck is capacity, not clarity. Who to hire first, Conway's law, team-size thresholds and the honest alternatives.
August 17, 2026
GPO-Tech
Let's discuss your connected product
Tell us what you are building, connecting or modernizing. Our Core Team will review your idea, current setup or technical challenge and suggest the best next step.
The Core Team is the group of senior engineers you talk to first. When a project needs more people, we bring in other teams and specialists we have worked with before, and we tell you who they are before work starts.
Phone
+372 5760 6060Choose how to start
Book a technical consultation
Schedule a call with our engineering team to review your idea, current setup or technical challenge.
Book a technical consultationSend project details
Tell us about your product, connection or modernization task and we will suggest the best next step.
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