Software development for iPadOS, iOS and macOS

Since the year the Mac was born I have been developing software for Apple Macintosh. And, also since it’s been available, I’ve extended that to iOS (iPad and iPhone) and tvOS (Apple TV).

On the server side I use Swift for developing web applications and back-ends for mobile applications.

I have built macOS and iOS applications for many customers for in-house and commercial use. For larger projects, or when additional expertise is required, I call on the assistance of other professional developers and designers.

Hello, Communicado 2.0

Version 2.0 of Communicado has been released. This is the iPad app I developed several years ago for people with aphasia. It was due for an upgrade. This version is a complete rewrite with a more modern look. For existing users the app will behave as before. It will just look slightly more, well, I think, beautiful. For editors of user content a couple of very useful features have been added.


Some of my macOS and iOS apps are available in Apple’s App store. In-between teaching and developing apps for clients, I produce my own apps. Most recently: Communicado.

Who am I?

My name is Fred Zuijdendorp. I’m living in Utrecht, The Netherlands, in a building from 1875. I have been a software developer ever since 1975. That’s a long time – how long can one stay active in this profession? Ask me again in 2075. I’ll keep on doing this as long as it’s fun and as long as I can keep up with the many changes in this profession. Actually, without these changes it would be boring.

In the past I was employed by the University of Amsterdam and by Apple. Two very different cultures, believe me. I’m happy to have been part of both. Since 1988, however, I’m enjoying my freedom being self-employed. I operated under different names: FMX software (me and a few colleagues), zdndrp (just me) and now effenix (still me). But it’s all the same. Me, practicing and (well, no longer) teaching software development.