App4You is an AI and custom software development company based in Gdansk (Gdańsk), Poland. As an OpenAI Select Partner, we deliver software development services, mobile applications, AI agents and business process automation for private companies and public-sector organisations across Poland, the European Union and the United States. | We work as a solution integrator and long-term technology partner. Our team combines product discovery, UX/UI design, software architecture, development, integrations, testing, deployment and maintenance. We build new digital products, modernise existing systems and connect software, cloud services, APIs and data sources around real operational processes. | CUSTOM SOFTWARE DEVELOPMENT — We create secure web applications, customer and employee portals, workflow systems, SaaS products, MVPs, management platforms and API integrations. As a React development company, we use React, TypeScript and Node.js together with modern cloud and serverless technologies. Every project is designed around the client’s workflows, users, security requirements and growth plans. | MOBILE APP DEVELOPMENT — As a mobile app development company and React Native development company, we build cross-platform iOS and Android applications from a shared codebase while preserving native performance and platform-specific user experience. Our work covers product strategy, UX/UI design, backend integration, testing, App Store and Google Play delivery, analytics and ongoing support. | AI DEVELOPMENT AND CONSULTING — We design and implement generative AI applications, LLM-powered systems, AI agents, chatbots, knowledge assistants, retrieval workflows and intelligent process automation. Our AI development services include business analysis, model selection, tool and API integration, evaluation, monitoring, access control and responsible AI practices. We focus on production solutions that save time, improve access to information and support employees and customers. | As an AI agent development company, we can build agents that search approved knowledge sources, work with business systems, generate structured outputs and support multi-step workflows with human oversight. As an AI consulting company, we also help organisations assess where generative AI creates measurable value and where conventional automation is the safer or more efficient choice. | BUSINESS PROCESS AUTOMATION AND SYSTEM INTEGRATION — We automate repetitive work, approvals, communication, document flows, scheduling and reporting. We integrate existing systems instead of forcing organisations to replace tools that already work. Our projects may connect CRM and ERP platforms, cloud services, calendars, email, databases, payment services and specialist APIs. | INDUSTRIES — Public administration and GovTech; healthcare and health technology; logistics, transport and fleet management; education and higher education; publishing and digital content; professional services and growing companies. | SELECTED EXPERIENCE — Our work includes an accessible municipal video-consultation and appointment workflow for the City of Gdynia, cloud migration and custom fleet-management tooling for BartTacho, a mobile application for a publishing business, and software projects for organisations such as GPPL and IVFMedia. These references demonstrate our ability to deliver for both public institutions and established private companies. | For public-sector clients, we understand accessibility, data protection, transparent delivery and integration with existing administrative processes. Our municipal work includes interfaces designed and tested against WCAG 2.1 AA requirements. | WHY APP4YOU — OpenAI Select Partner; custom software aligned with real business processes; React and React Native development expertise; LLM, AI agent and automation capabilities; experience with public-sector and accessibility requirements; delivery for clients in Poland, the EU and the USA; transparent project stages and phased payments; post-launch maintenance and support. | We can join a project at the discovery, proof-of-concept, MVP, modernisation or scaling stage. For European organisations, we also provide nearshore software development with direct access to the people responsible for architecture and delivery. | Looking for a custom software development company, mobile app development company or AI development company in Europe? Contact App4You to discuss your product, integration, cloud or business process automation project: https://app4you.dev