---
title: "App Developer & Full-Stack Expert"
canonical_url: "https://robocitrus.com/en"
last_updated: "2026-07-19T00:10:27.686Z"
locale: en
meta:
description: "Flutter app development, backend & full-stack solutions from Germany. Scalable apps, backends and websites for startups and businesses."
"og:description": "Flutter app development, backend & full-stack solutions from Germany. Scalable apps, backends and websites for startups and businesses."
"og:title": "App Developer & Full-Stack Expert"
"twitter:description": "Flutter app development, backend & full-stack solutions from Germany. Scalable apps, backends and websites for startups and businesses."
"twitter:title": "App Developer & Full-Stack Expert"
---
RoboCitrus - Home
**Ready to rock? π**
# **Anyone can build apps. Systems that rock? That's my thing.**
From idea to finished startup. App, backend, website - all connected, all scalable.
[That's me!](https://robocitrus.com/en/about)
**Solutions**
## **What I build **and why it's different
Nothing's impossible! π While others are still planning, your system is already running. I don't build apps, I build systems. From the first line of code to the scalable startup. Full-stack, full power, full ready to rock! πΈ
[π**Apps that scale!**
Others tinker, I build solutions! π You don't just want an app, you want a complete system. I build you Flutter apps with Clean Architecture that are designed for growth from day 1. No quick & dirty solution, but systems that still rock with 100,000 users!**Learn more ****Apps that can grow****Clean Architecture from the start****Flutter + BLOC = Pure performance**](https://robocitrus.com/en/leistungen/app-entwicklung)
[βοΈ**Backend systems with power**
Everyone cooks with water, me too! βοΈ Your app needs a backend that can keep up? GoLang, Microservices, Kubernetes - I'll build you infrastructure that scales. - GoLang backend development - Microservices architecture - Kubernetes & Cloud deployment**Learn more **](https://robocitrus.com/en/leistungen/backend-entwicklung)
[π»**Web Development & Landing Pages**
Your app needs a website? Vue.js, Nuxt.js, WordPress - I'll build you web solutions that perform! π» Landing pages that convert, admin panels that work. Everything from one source, everything perfectly tailored to your system! - Landing pages that convert - Admin panels & dashboards - Vue.js & Laravel development**Learn more **](https://robocitrus.com/en/leistungen/web-entwicklung)
[π**Flutter & App Coaching**
Personal 2-hour sessions for your app projects. Pair programming, problem-solving & tech support. - Flutter & app development support - Pair programming sessions - Code review & best practices**Learn more **](https://robocitrus.com/en/coaching)
**My own product**** Open Beta Β· Live **
**iOS Β· Android Β· Web **
## **DragonBoat Hub **
My own app for dragon boat teams. Sorts the lineup, tracks the session, handles race day admin.
[Download on the**App Store** App Store](https://apps.apple.com/app/dragonboat-hub/id6751578999) [Get it on**Google Play** Google Play](https://play.google.com/store/apps/details?id=com.robocitrus.dragonboatpro.dragonboat_app) [Open in**Browser** Web App](https://app.dragonboathub.de)
[**See the case study **](https://robocitrus.com/en/projects/dragonboat-hub)
[DragonBoat Hub case study](https://robocitrus.com/en/projects/dragonboat-hub)
[**App, Web & Backend Development****Hundeo**
Hundeo is an innovative dog training app offering over 500 tricks, games, recipes, guides, and courses. Its unique selling point is the integration of artificial intelligence that personalizes the learning process. This enables flexible and effective training tailored to each dog's individual needs. Hundeo revolutionizes dog training through cutting-edge technology and personalized training approaches.**Flutter****KI-Integration****GoLang Backend****Microservices**> *"I find the collaboration to be very professional and pleasant. I was particularly impressed by your structured approach and clear communication. You not only quickly understood our requirements but also implemented them efficiently and purposefully. The result speaks for itself and fully met our expectations. I was especially struck by your flexibility in accommodating individual requests and finding solutions. Overall, I am extremely satisfied with the implementation and can only recommend the collaboration." *](https://robocitrus.com/en/projects/hundeo) [**App & Backend Development****QUESS**
QUESS is a Bluetooth device with an app that makes gut feelings measurable. Users ask a question, hold the sensors and get an answer. Smart AI provides even more precise results.**Flutter****Bluetooth/BLE****Serverpod****Full-Stack Dart**> *"We found the media agency Robocitrus through a Facebook post and quickly agreed within the company that we had found the right freelancer for our app project. We have now been working with the agency for almost a year and will also be awarding further app development contracts to the agency. The collaboration so far has been consistently highly professional and very structured. Even with special requests and changes, the agency was always approachable, brought in its own innovative suggestions and ideas and implemented them extremely competently. The collaboration was always extraordinarily trustworthy and at a very high professional level. We always felt like we were dealing with our own highly motivated employee. For our startup, it was a fortunate coincidence to go this path together with Robocitrus. Top: 5 out of 5 stars are fully justified." *](https://robocitrus.com/en/projects/quess) [**Ecosystem: App, Web Dashboard & Backend****Baustellenplaner**
For a fiber optic civil engineering company, I developed a complete digital ecosystem: a mobile app for Android and iOS, a web dashboard for management, and a powerful backend. All from a unified codebase. The system replaces outdated processes and WhatsApp workflows with a well-designed digital solution for office and construction site.**Flutter****Serverpod****Full-Stack Dart****Offline-First****Ecosystem**](https://robocitrus.com/en/projects/baustellenplaner) [**Web Design, Development, Content Creation & Hosting****Wasserradler**
A modern company website for water bicycle rental β with appealing design, easy operation and responsive implementation to strengthen the company's online presence.**Vue.js/Astro****Tailwind CSS****SEO****Hosting**> *"We had our website created by Maxi. Agreements were kept and the site was developed as requested. He's already commissioned for follow-up projects." *](https://robocitrus.com/en/projects/wasserradler) [**Web Development and Backend****ImmoPlanet Schellenberg**
A professional company website for a skilled trades business in Dortmund. Electrical installation, renovation, flooring and more. The site showcases completed projects with before-and-after images and makes it easy for customers to get in touch.**Nuxt 4****Go Backend****Tailwind CSS****SEO**> *"Responds to requests and implements them as quickly as possible. Thank you for the great collaboration. I can recommend the agency to everyone." *](https://robocitrus.com/en/projects/immoplanet) [**App Development & Design****Fussballhero**
Fussballhero is a platform that enables football-enthusiastic children and teenagers to convert their real performance on the field into virtual achievements β developed as a lean MVP to cost-effectively test an innovative idea.**Flutter****Firebase****Gamification****MVP**> *"Max was extremely professional throughout our joint project. The result totally convinced me and I am very satisfied with it. The collaboration was also a lot of fun! Can only recommend." *](https://robocitrus.com/en/projects/fussballhero) [**Web Design & Development****Drachenbootevents**
A modern company website for presenting and organizing dragon boat events β optimized for user-friendliness and mobile use.**PHP****Bootstrap****SEO****Hosting**> *"Fast and professional implementation of my ideas. Furthermore, the website could be designed even more purposefully with your know-how. Not only the creation but also the technical support of the website for later changes is great. Always available for questions and customer requests are implemented quickly. I am very satisfied with the result and can recommend the collaboration. If you want to create a website or have your existing one revised, Maxi is your professional contact." *](https://robocitrus.com/en/projects/drachenbootevents)**Testimonial**## **What my clients say** Experience report from app development coaching. > *Highest recommendation from my side, without any ifs or buts. Maxi is your man if you want to develop your own app.***CB****Christian Bachmann** App Development Coaching ## **Let's Connect! π**### **Ready for your next project? **** Let's get started!** #### **Maximilian Flechtner **[flechtner@robocitrus.com](mailto:flechtner@robocitrus.com) [ +49 0176 41766223](tel:+4917641766223) ### **Let's get started** Tell me about your vision β just drop me an email or use the contact form. Let's plan your digital success together! πͺ [Send me an email](mailto:flechtner@robocitrus.com) [Contact Form](https://robocitrus.com/en/kontakt)