I love making apps*
Solid Links is the professional identity of Erik Romijn, App Maker from Amsterdam, The Netherlands. I make web apps and apps for mobile devices. Most of my work relates data-driven apps: making data, existing or new, accessible, usable and friendly.
I mostly build native iPhone applications, and web applications (usually with Python and the Django framework). But I don't stop there - my experience includes anything from computer networks to system administration to databases.
I do a mix of projects for clients and my own independent work. Some in partnership with others. I regularly speak at conferences, meetups and other events. I write a blog on what keeps me busy.
Get in touch with me through:
My independent projects
Amsterdam Like a Local
Amsterdam Like a Local lets people discover Amsterdam in a new way.
Amsterdam Like a Local lets anyone talk for 30 seconds about something they know about Amsterdam, and tag the recording with a location. They can talk about a special story they know, or anything else they feel is worth sharing.
On the other side, anyone can listen to the recording. But, the only information a listener gets are the location and categories. There are no descriptions or titles. There are no names or aliases. There is no way to know who made a recording, or whether two recordings are made by the same person. The only way to learn anything at all, is to listen, making it a delightful surprise every time.
iPhone english free
Openbaar Vervoer [Dutch] [English]
Openbaar Vervoer is the app for realtime status of Dutch public transport.
Where's my tram? Is there some disruption? Are other lines still running properly? When will my bus arrive at that stop? Did I just miss my bus because it left too early, or is it late and should I wait? Now it's easy to answer these questions, and many more, with Openbaar Vervoer for the Apple iPhone: the app for up to date status of Dutch public transport. With Openbaar Vervoer, real time data of almost 3.000 Dutch public transport lines is just a tap away.
iPhone dutch & english paid open data
Bike Like a Local
Bike Like a Local is the iPhone app for biking tourists in Amsterdam.
For tourists coming to Amsterdam, the best way to discover the city is by bike. But, Amsterdam is also a very busy city, with 800.000 bicycles and many cars, trams and other vehicles. Bike Like a Local is the iPhone app for biking tourists in Amsterdam! It helps you bike around Amsterdam safely, tells you where and how to park your bike, and helps you to remember where you parked your bike.
Won the 2nd price in mobility in the Apps for Amsterdam 2 open data app contest.
iPhone english paid open data
Korting in kaart
Korting in kaart helps public transport users to discover which discount card works best for them.
In recent years, there's been a huge growth in the variety of transport discount cards. It's become almost impossible to discover which card would work best for you by simply estimating. You need solid numbers.
Korting in kaart takes the travel history registed by the public transport chip card and calculates all possible scenarios. The travel history contains all data necessary to calculate the discount that every card would have given for every trip, helping the user to make a good decision in a simple and fast way.
web dutch free / donations
Sola [Dutch] [English]
Sola helps users with estimating whether it's profitable to install solar panels on a roof, in an simple and fun way.
Sola was built to provide a simple, fun, and fast estimate of whether it pays off to install your own solar panels. No complex terms or calculations; just enter the size of your roof, measure the orientation by holding your phone on the roof for a moment, and get all the numbers.
Sola also tells the user whether any subsidies are available, based on your location. That can make a huge difference in the profitability, as subsidies are usually quite significant.
Won the 3rd price in the Apps voor Nederland open data app contest.
Also featured in an interview on BNR.
iPhone dutch & english paid open data
BezorgBuddy [Dutch] [English]
BezorgBuddy lets users track their PostNL package deliveries.
BezorgBuddy can track both national and international packages sent trough PostNL. For the sender, there's a built-in barcode scanner, which saves time when entering new packages.
iPhone dutch & english freemium & ads
Zwemwater Noord-Holland [Dutch] [English]
Zwemwater Noord-Holland shows information about open air swimming sites in the province of Noord-Holland.
Zwemwater Noord-Holland shows not just which sites exist, but also whether they are safe for swimming. The province of Noord-Holland frequently checks all official sites for dangers for swimmers.
The app also shows which facilities are available, like public toilets, first aid, or whether dogs are allowed.
Won a encouragement price in Apps for Noord-Holland.
iPhone dutch paid open data
Erik's Pony Checkup
Erik's Pony Checkup helps developers of Django web apps to improve the security of their products.
Django is a framework to build web applications, using the Python programming language. Erik's Pony Checkup checks various externally visible security aspects involved in running a Django website, like the correct use of HTTPS and various settings that can help security.
web english free
Amsterdams Lokaal [Dutch] [English]
Amsterdams Lokaal gives users simple and easy access to the local news in Amsterdam.
Amsterdams Lokaal uses open data from AT5, Amsterdam's news and current affairs channel.
It shows not only the latest news, but also events that happened near your current location. And if you see something newsworthy yourself, you can use the app to send the tip straight to the AT5 editors.
iPhone mostly dutch paid open data
Energielabel-app
Energielabel-app provides insightful data about energy ratings (energielabels) of buildings in Amsterdam.
Energielabel-app helps users to discover details of their own energy rating. In addition, it will compare the rating with other ratings in the area. By doing this, building owners who score very low compared to the rest of their neighborhood will be motivated to improve their rating.
Built in a team of 5 for Apps for Amsterdam, where it won the first price and the audience price.
web dutch free open data
Verleden Kijk (no longer available) [Dutch] [English]
Verleden Kijk showed historical images of Amsterdam around the user's current location.
The images in Verleden Kijk were anywhere between a decade and a few centuries old and came from the Amsterdam city archives.
Verleden Kijk is no longer available due to a copyright misunderstanding.
iPhone dutch & english free open data