SOFTWARE DEVELOPER · HAMBURG

I BUILD THOUGHTFUL SOFTWARE TOOLS AND ENGAGING EXPERIENCES

Portrait of Jonah Großhanten, software developer based in Hamburg

I create products that combine solid engineering with clean design. From property management tools and macOS utilities to interactive data visualizations and mobile games.

SELECTED PROJECTS

Wonario

WONARIO

Modern property management platform

  • Cloud tool for landlords and property managers
  • Centralized dashboard for properties, tenants, investors
  • Built-in ticketing for maintenance and repairs
  • Direct tenant communication and partner coordination
VISIT SITE →
SnoozeBar

SNOOZEBAR

Smart sleep scheduling for macOS

  • Menu bar utility for power management
  • Quick sleep timers that survive restarts
  • Flexible scheduling with system integration
  • Lightweight, native macOS experience
VISIT SITE →
Flow

FLOW

Team wellbeing tracker

  • Internal mood barometer for organizations
  • Tracks employee sentiment over time
  • Visual dashboard for HR and team leads
  • Prevents burnout, strengthens team connection
VISIT SITE →
Minuvo

MINUVO

Privacy-first subscription tracker

  • Local-only recurring payment manager
  • Track bills with flexible cycles and categories
  • Analytics: monthly costs, trends, breakdowns
  • CSV export, no cloud, no bank connections
VISIT SITE →

JOSCHA2 – RETURN OF THE CHORES

Space shooter meets household tasks

  • Arcade game where chores chase you through space
  • Progressive difficulty with unlockable ships
  • Power-ups: freeze, bomb, shield, multishot
VISIT SITE →
Aural Atlas

NATIONAL AURAL ATLAS

The emotional map of anthems

  • Interactive world map of national anthem emotions
  • Based on 2025 research (Toiviainen et al.)
  • Visualizes valence, energy, tension, happiness, fear
  • Built with React, TypeScript, MapLibre, D3
VISIT SITE →

CLIENT PROJECTS (NDA)

Custom tools and sites

  • Business dashboards and internal tools
  • Responsive marketing websites
  • Privacy-focused, maintainable solutions

EXPERIMENTAL PROJECTS

Games, data, and sound

  • GPS mobile game: paint the world by walking
  • Neuro-activity game with musical interaction
  • Exploring playful intersections of technology
CEO & FOUNDER

I lead X-Concapps GmbH, a software company building custom solutions for web, desktop, and mobile. Projects like Wonario and Minuvo were released through the company.

10+ PROJECTS
500+ CLIENTS
7 PRODUCTS

LET'S CONNECT

I'm open to collaborations, product work, interactive data projects, and game development.

Let's build something meaningful together.

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