Sergio
Díaz
Mobile & Full-Stack Developer
Flutter · iOS · .NET · AI Agents
Andorra — available
Apps and digital products designed, built and operated by one person — from architecture to the app store.
Career
2019
Avanade · Logaritme
Early years: Java and consulting
2020
Bdr Informática
Full-stack product work
2021
Ohtic · Freelance
.NET and React; mobile with Flutter and iOS
Today
Own products
GetaLink · Southpaw · agentdeck
Freelance Mobile Developer specialised in Flutter and native iOS (Swift, SwiftUI). I've built DigiAcción's mobile app and my own products like Southpaw and LiftIQ. I work end-to-end: from architecture to App Store and Google Play deployment. With 6+ years of prior full-stack experience (.NET, React, AWS), I bring technical context most mobile devs lack.
AI & Agents
Claude Code · Claude Skills · AI Agents
Mobile
Flutter · Dart · Swift · SwiftUI · UIKit
Backend
.NET 8 · MySQL · Entity Framework
Frontend
React · TypeScript · Next.js · Tailwind
Tools & DevOps
Docker · GitHub Actions · Linux VPS · AWS
Projects
Destino Decision wheel in SwiftUI with a widget, Siri/Shortcuts and a one-time purchase; registered in App Store Connect with the whole listing built via API, now on TestFlight
2026 · app Discalia Herniated disc rehab app live on the App Store: daily pain log, an AI-generated routine from your medical report and hydration tracking, with subscription
2026 · app LiftIQ iOS app to track barbell training: sets, RPE, progression and personal records
2026 · app DigiAcción Cross-platform Flutter app developed for DigiAcción, fully integrated with their backend
2024 · app Fundenza Web development for a consulting firm specialized in mergers and acquisitions
2024 · web They've trusted me
Singular Bank Flax & Kale DigiAcción MotoGP (Dorna) Acciona PayRetailers Bella Aurora Generalitat de Catalunya
In black, mobile clients. In grey, prior full-stack work (.NET, React).
Marketplace Under construction
Software and AI tools, on sale soon.
Ready-to-use products and AI-oriented tools, built and maintained to the same standard as the portfolio projects.
Visit marketplaceContact
Let's talk
Available for projects — UTC+1 (CET)