Aapo’s selected works

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

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What I faced

  • 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.

What I did

  • 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.

What came of it

  • 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.

Current status

  • Up and running. Subscriber count increasing steadily.
  • Plans to add more languages and more countries with their holidays.
  • Plan to start charging money for at least some of the calendars.
  • I have recieved serious offers from interested parties to purchase the website.