This page gives an overview over the recent projects I have been working on.
This is not a list of all projects I worked on, as older projects (> 2-3 years) will be thrown out. For a list of my work experience, please visit the about page.
I am currently working on…
- two client projects (Java and frontend design)
- … a personal project (iOS app).
Since the end of 2009, my work has been focused on iOS development.
textunes (eBook Reader)
- App Store Link
- Client: textunes GmbH (since 2011 part of the Thalia)
- Duration: Sep 2011 until May 2012
- Category: eBooks
textunes is an app for buying and reading eBooks.
Created by a small startup in Kreuzberg, Berlin, the textunes GmbH was acquired by Thalia in 2011, Germanys second-largest bookseller.
The textunes app has two major parts: a shop to download samples and buy books, and a reader to view the books.
Despite hard competition in the eBook apps market with challengers like iBooks, Kindle or Kobo, textunes stands out through features like
- flexible store concept called “channels” to group books for different interests; much imagery transports emotion
- cloud-like backend to access and restore books accross different devices
- versatile types of content, including audio-, text-audio-books and interactive text books (e.g. with questionaires)
- apps for both iOS and Android (OYO).
The textunes app is actively developed by a small team, and has grown to a quite large and complex application, with more than 250k lines of code.
During my 1.5 year engagement, I have been working on nearly every part of the app:
- system architecture for
- a new content processing system to load different book types (audio, interactive, ePub compatibility)
- channel-concept to wrap and abstract from the webservice API
- a system that abstracts different app features as items (books, channels, favorites, authors etc.) to flexibly combine and interact with them
- smart view controller hierarchy to avoid code duplication and share visual appearance throughout the app
- asynchronous communication with webservices, parsing of responses, handling of errors
- implementation of page-based layout for books (before there was only scrolling)
- extensive debugging and bugfixing in every part of the app
- performance analysis and optimization
- agile project management methods with Scrum, code review, pair programming etc.
Technolgies in use
- Cocoa, UIKit, CoreAnimation, GCD, ARC, StoreKit, WebKit
- 3rd-party libraries
- git, Jenkins
- JIRA, Confluence
Oetinger children’s books
- Client: textunes GmbH
- Duration: Sep 2010 until May 2011
- Category: eBooks
Oetinger is the biggest publisher of childrens books in Germany.
In autumn 2010, work started to create several apps for several popular book titles:
- Helma legt die Gockel rein (recommended)
- Die Olchis aus Schmuddelfing
- Rat mal, wer das ist!
- Bist du meine Mama
All apps contain richly animated scenes, sound effects and a read-aloud-feature, clickable and moveable elements and a small game.
In spring 2011, Helma and Olchis where both in the top-ten of the App Store Charts in Germany (category “Books”) and mentioned by Apple in New and noteworthy.
At the start of the project, dedicated tools to create eBooks (like HTML editors with strong CSS3 support) did not yet exist.
Therefore we created our own set of utilities:
- a tool to convert Flash movies into HTML and CSS3 (long before Adobe published similar products)
- a framework to easily create interactive books with clickable elements, animations and sound
- implementation of device-specific features like device rotation
- native audio support to play muliple audio files concurrently
- project management, App Store releases, version compatibility (iOS 4.0 / 4.1 / 4.2)
Technolgies in use
- UIKit, WebKit, CoreAudio
Like most developers, I also have many own unfinished projects in the oven, which get regularily postponed by contract work.
Unfortunately, none has made it to the app store yet.