OpenTopoMap Viewer
OpenTopoMap renders topographic maps from OSM and SRTM data. The style is based on German government maps, with a focus on landmarks and contrasting map colors.
This FOSS Android viewer uses osmdroid to browse these maps on a mobile device. It features offline caching and import of GPX files.
Prometheus Informatics
At Prometheus I am working on our mobile logistics solution on Android, including truck navigation based on the HERE SDK.
Magneds is the number one in Digital Sales & Loyalty Solutions. We work for clients such as FrieslandCampina, Heineken, Coca-Cola, Mondelez, Texaco, AVIA and Pathé.
Our solutions: smart digital sales promotions and cashbacks, innovative loyalty promotions and customer loyalty & engagement platforms.
Our powerful combination of marketing strategy, innovative digital technologies and creativity allows brands to create valuable interactions, drive consumer demand, accelerate growth and create insights in consumer behavior.
At Magneds I've worked on several loyalty apps, like Eurosparen by FrieslandCampina, the award winning Heineken Biertegoed and Pathé All Stars.
Plant Hero
Plant problems? Not enough growth? Insects? Our Plant Heroes are here to help you for FREE in less than 24 hours. The app has been developed for Sigrow in collaboration with plant scientists from Wageningen University.
Sigrow Cloud
The Sigrow Cloud collects environmental data for crops all over the world. This data is exposed over web services to dashboards, notification services, mobile apps and third-party applications like the Botrytis Monitor by B-Mex.
Back-end technologies implement RESTful endpoints in Python/Flask. The common front-end is a web application in HTML/CSS/JS.
Dynamic Nutrients
The Dynamic Nutrients app generates the optimal watering and fertilization schedule for your plants. It has been developed for Sigrow in collaboration with plant scientists from Wageningen University.
This app is dynamic in several respects, with its ever growing user history, and an example of using data binding and view recycling to prevent the slightest lag.
Ersa
The core functionality of the Ersa library is all about calculating the dew point from temperature and humidity data. The dew point is used to assess environmental risks, like mold and corrosion, as well as to predict material preservation (e.g. in archives and art collections). The Ersa solution collects data from LoRa connected sensors and processes this data to provide insight into environmental conditions.
German License Plates
This app looks quite ugly, don't you think? Yet it proves the striking truth that the simplest ideas are often the best. Hundreds of thousands of users have found out the origin of German cars with this app.
The first version was released in 2011, when I was taking my first steps towards full discovery of the Android universe.
Psychometric Tests
I tend to be somewhat skeptical of the use of these psychological tests. Nevertheless, they are fun to develop and interesting enough to play around with.
Linux
Penguin Power is indispensable. In general I prefer to develop on Linux systems. Apart from that I deliver Debian derived distributions to meet customer specific needs. I also create software packages using the Debian build system.
My natural habitat is scattered with Raspberry Pi projects, some of which are interesting enough to be translated into other languages.
libGDX
Although I'm not much of a gamer myself, building games in my spare time is challenging and fun. My favorite Java framework is libGDX, allowing me to develop for Android and desktop using the same code base.
The example shows a simple attempt to create something even more annoying than the notorious bird.
Cellular Automata
Back in nineties, as a young biologist working in IT, I was fascinated by these (simplifying) simulations. I created a Java applet for the spatialized prisoner's dilemma. It became a top 25% web applet, which made it easier for me to start a career as a software engineer.
Java applets are long dead and gone. When I started with Android years ago, I decided to build a mobile app based on the old Java code. It was my very first Android app, so it sort of became crucial for the second time in my life.
I have revived the original concept in JavaScript: prisonersdilemma.sergehelfrich.eu. It is still being used in education.
SOS4US
In case of emergency this app immediately and silently alerts your personal network when you need it most. SOS4US was commissioned by Lodgecal.
Q-Fieldservice
Starting in 2011, this was one of the more challenging projects from the past few years. In retrospect I'd say that back then the Android platform was hardly mature enough to seamlessly integrate with a full-blown business solution built in Microsoft .NET. It required a lot of truly artisanal programming. Yet it worked out!
GitHub
My life is for a significant part about building things and sharing knowledge, so contributing to GitHub projects appears to be inevitable.