Jeroen Ransijn

Hello, I am Jeroen Ransijn

I have experience building and designing booking engines, checkouts, mobile apps and games, audio apps, maps with live data, product filters, live previews, admin panels, audio questionnaires and more.

Reach out to me on Email, Twitter or LinkedIn

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1FX app on iPhone 6

1FX – be the DJ


During Make School Summer Academy 2015 in San Francisco I've build 1FX, a live music filtering app. The features are:

  • Combine 6 powerful music effects that DJs use
  • See live music visualisation
  • Play songs from your music library
  • All effects can be triggered at the same time

I started building it at iOSDevCamp, a hackathon in Palo Alto. It actually won “Best DJ app” ​ at this hackathon. The audio processing is done with Core Audio and audio units. The app is mainly written in Swift. However, since Core Audio is essentially a C api, I had to write some parts in Objective-C/C because Swift offers terrible support for some audio stuff.

One of the biggest challenge I had to overcome was to do offline rendering of the track and extract the BPM.

View app website or download the app on the App Store

Sunny Cars website on iPad

Sunny Cars

Started at Aan Zee

Adaptive website, booking tool and partner tool (for partners such as D-reizen and ANWB). I worked as Front-end developer and designer. In this project we use Scrum working methodology and I have been on the team since the third sprint (currently finished the 7th sprint). Currently Sunny Cars had a soft launch, complete launch in The Netherlands and Germany will be soon.

Apart from the website and booking tool one of the coolest parts was the partner tool. Partners such as D-reizen and ANWB have the ability include a responsive iframe on their website with the complete booking functionality, all in their style. With a custom admin panel they can change the logo, colours, border radius of the complete booking tool, this includes every step in the booking process. As well as seeing the live result, a live preview is also available in the aforementioned admin panel, which contains the most common UI elements and partner widget.

View live website or read more about the usability improvements (Dutch)

De Groene Kapstok

Started at Aan Zee

Responsive website for a green initiative by Gemeente Haarlemmermeer. The complete website came together in a two week SCRUM sprint. Filled with information how schools can optimize their environmental awareness and hands on tips tricks to make this happen. The content of the website is focused on school staff.

View website

Ransijn & De Graaff


Responsive website for my parents company. Their clients love how clear it tells their story. My parents use it to explain their financial service in a clear and elegant way. I worked together with my parents, a photographer and a copy writer to bring a unique solution in a field where you least expect it.

View website

Drop It! Multiplayer Game press release photo

Drop It! Online Multiplayer Game

Started at Aan Zee

Mildly successful game, ranking in the App Store top ten on the first day of the launch. What began as a side project with Rick Groenewegen, grew out to be much more. Inspired by WordFeud, Rick developed the multiplayer backend specifically for this app, I designed the application and website. Drop It! was featured on AppEvent multiple times.

Drop It! is a connect four game you can play with your friends or complete strangers. Both iOS and Android users can play the game. There is a chat feature in which you can talk to your opponent. A list of achievements make it fun to play the game. And there is a leaderboard in which you can compare your scores to your friends and the world. The app has been translated into 8 languages.

View website or download the app

AllUnited Adaptive Web Templates

Started at Aan Zee

The design and implementation of an adaptive web template for clubs at AllUnited. Consisting out of a user friendly adaptive design, a completely rewritten CMS backend and numerous process optimisations. All these combined will give AllUnited a huge leap forward and will bring innovation to hundreds (sport) clubs.

View online demo

Valk Calendar

Started at Aan Zee

Van der Valk employees can check their schedule, plan vacations, apply for free shifts and more in an all sleek and responsive calendar. On mobile the website feels almost like an app due to the implementation of some of the latest HTML5 technologies.

DB Bruist mobile application

Starting at Aan Zee

Mobile application to find activities in the area from Leiden to Haarlem approximately. I worked on most of the usability together with Bart van de Biezen. Moreover, I designed the app for mobile and tablet. Finally the app was launched in front of hundreds of local entrepreneurs in an event specifically hosted for this launch. The project has sadly been discontinued a while back.

node-webkit icon

Node-webkit icon design

for Intel Open Source Technology Center

Reach out to me on Email, Twitter or LinkedIn