Aapo’s selected works

Please note that only a small fraction of Aapo's projects can be shown here in public.

WebCal

In 2008 I needed to have European week numbering (ISO 8601) in my calendar application and mobile phone for business purposes.
Week numbers are often used in Finland for setting business appointments.
I did not find a suitable solution.

I decided to create a calendar service myself.
I searched if others had similar needs. I found dozens and dozens of questions in discussion boards where different people wanted these data in their calendars. There was a real need for this type of service.
The system must be automatic, work with any application and be always up-to-date. It should require only one press of a button from the user, then he can forget about it.
I researched holidays of several countries. It proved not to be too complicated to create a program to calculate the date for each holiday. There are only four basic methods how these dates are calculated.
I used MySQL to store the data and cache calendars (for performance), PHP to create the calendars and CSS & jQuery for the web user interface.
First I released a working prototype in one discussion board. Soon my calendars had thousands of subscribers.
There was much positive feedback. I studied which calendars were used the most, tested with many new applications and mobile phones, worked on improving the user interface etc. Late 2010 I moved the service to its own domain webcal.fi.

WebCal.fi became much more popular than I had anticipated.
There are almost 20 million weekly downloads (over 1 terabyte) (July 2017).
Supports nine languages (English, German, French, Spanish, Portuguese, Italian, Dutch, Swedish, Finnish).
Provides about 70 different calendars, such as Week numbers, Sunrise & sunset, Holidays, Solunar calendar, Moon phases, Weather prediction, UN obervances etc.
About 300 000 users (July 2017).
Several WebCal.fi calendars listed at Best of iCalShare.