Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning.

Daniel Bleisteiner


Berliner! Father and husband! Music lover, Internet enthusiast, Java professional, iOS coder and iPhone lover...

I have been lucky enough to make a hobby my profession. My interest in computers started early with some programming in Basic for a KC 87 – my very first computer. Over the years I've used many devices... and here we are now, holding tiny computers in our hands that are more powerful than ever and a life without them is hardly imaginable.

  1. Born in Bad Salzungen, Germany

    I've been born in Thuringia and moved to Berlin only a few months later.

  2. School in Berlin, Germany

    At the age of 6 I've started with school and focused on mathematics and physics in High School.

  3. Computer Science at Technical University of Berlin

    After one year at the german army I've started studying Computer Science in Berlin. My focus has been on Theoretical Computer Science and Computer Graphics.

  4. Internship at Business Online AG

    At my first internship I've deepened my early knowledge of HTML, CSS and JavaScript. The company no longer exists today.

  5. Internship at MetaObject GmbH

    A few months later I dived deeply into PostScript, PDF and Objective-C. At this time I've also started to use Apple Computers and quickly fell in love with their OS and its superior UX.

  6. Software Developer at MetaObject GmbH

    For the next 2 years I further improved my knowledge and could finally call it my first real job. The small company later broke up and I've continued my work at its successor.

  7. Lead Software Developer at cidentigo GmbH

    I've focused on the development of a PostScript pipeline that produced professional printable catalog content by generating PDF documents from templates and Database content. We used WebObjects in Objective-C and later switched to Java.

  8. Diploma of Computer Science at Technical University of Berlin

    My final diploma in Computer Science was named “Generic Content Management System for eXtended Business Objects” and laid the foundation for many projects. Since the early years of this century I've focused on Generic Software Architecture that is easily extendible and flexible. These concepts are still relevant for my daily work and have been adopted for many projects in similar ways.

  9. Senior Software Developer & Team Manager at Luxoom GmbH

    My job at luxoom focused on a small startup called “wishdom” which never really took off. It used Magnolia as CMS and Liferay for its platform – both technologies, I wouldn't use anymore.

  10. Senior Software Developer & Team Manager at GmbH

    After the startup fell apart I've been pulled into ECG and a totally different market: European Funding Management (ESF, EFRE and others). The company has been active since the late 90's and was quite ambitious with an online-only approach for funding management. I've had the chance to build the next generation of “Eureka” – written in Java using modern web technologies and an Oracle Database for the backend. It was the perfect project to implement and adopt my previous experiences with flexible and extendible software architecture.

  11. Lead Software Engineer & Team Manager at GmbH

    After the frist few years as senior developer I've given the chance to lead the project – and still continue to do so. “Eureka” is currently used in its 5th iteration and I'm eager to explore even more possiblities and new markets. The software uses a very customizable approach with PlugIns, Workflows and a flexible State-Management for nearly unlimited types of Business Objects. I'm still deep into Java and related technologies like CDI, JavaEE, JPA, JSF, SpringBoot and modern front-end development using Vue.js and others.

That's it so far. I'm always eager to learn and create new things and I can't tell what I'm doing 10 years from now. But it will likely be related to modern technology and all the things made possible.


With the Apple Watch Series 8 and the Ultra Apple introduced a new temperature sensor, which may be used to track the temperature at your wrist. While you're sleeping with the watch, it measures the temperature every few seconds and starts tracking your body temperature.

Sadly that data can only be found within the health app – a handy widget showing these stats on your homescreen is missing. And that's where Wristy comes into place! The app reads that data from HealthKit and offers you three different sizes of a widget. So you can keep an eye on your temperature at all times and get a quick picture in the morning.

The app has been developed in Swift and uses SwiftUI as well as Swift Charts, which has been introduced with iOS 16. By using these rather new frameworks I've been able to develop my idea and publish it to the app store quickly.


The Settings of Wristy
The Widgets of Wristy
The Widgets in Dark Mode
The Infos of Wristy


Wristy show the temperature at your wrist as widget on your homescreen!

NOTICE: This data is only gathered if you wear an Apple Watch Series 8 or Ultra while sleeping. If you don't have such data yet the widgets will show you a random preview of their functionality.

The app allows you to authorize the data from HealthKit and shows it as a small, medium or large widget on your homescreen. It is kept plain and simple by design and includes only the most necessary things.

In the near future I plan to add other data but the temperature at your wrist from HealthKit into the app to make even more widgets possible – but first things first.

The app as well as the widgets fully support darkmode and are available in english and german.


Here are some links related to Wristy.


I've started development of GeoLicious in 2013 to build an app mainly for my own purposes. I wanted to track my location in a way similar to Foursquare or Facebook but much more private. In 2013 there was no app available that nearly did what I wanted. So I've put all my ideas into this personal project and kept it running till 2017.

The app has never been a real success in terms of revenue from the AppStore. I've invested much more time than I've got money back in return. On the other hand I've never invested real money to promote the app. GeoLicious has always been a private project maintained for personal use and for further learning iOS development.

In the end I've published the complete SourceCode at GitHub under MIT License. Maybe someone has the time and desire to continue this project written in Objective-C.

Screens (iPhone)

Map of all Locations
Previous Check-Ins
Location Settings
Application Settings
Map of all Locations
Map of all Locations
Previous Check-Ins
Previous Check-Ins
Location Settings
Location Settings
Application Settings
Application Settings

Screens (iPad)

Map with Previous Check-Ins
Application Settings
Location Settings
Search for Locations
Previous Check-Ins
Previous Check-Ins
Application Settings
Application Settings
Location Settings
Location Settings
Search for Locations
Search for Locations


GeoLicious has been developed to allow offline and private location tracking. It offers all you need to check in to locations, track your everyday movement and keep a log of all the places you have been in your live. All your checkins are presented in a beautiful interface offering a freely browsable world map, a searchable list of all your checkins and locations and some simple but effective settings for your convenience. Your privacy is considered valuable – GeoLicious will never send any data without your permission and does not collect any hidden data.

GeoLicious also allows you an active connection to Foursquare. If you like, you may sync selected locations to the Social Network. This works for manual checkins as well as automated checkins in the background and makes it easier as ever to defend your mayorship. Of course this functionality is fully optional – you may disconnect Foursquare at every time and reconnect later if desired.


The following list names most of the more prominent features.


Here are some relevant links related to GeoLicious.


Over the last years I've started many things. Some of my social profiles are still active and updated regularly. Here is a small selection of these.

You may find several others in the World Wide Web – but most of them are outdated and abandoned.

If you wish to get in touch with me you may also write to directly.

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Responsible for the content

Daniel Bleisteiner (private), Berlin, Germany,

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