Colour by Numbers is a permanent light installation in the tower at Telefonplan in Stockholm, Sweden. Everyone can change the colours in the tower with their mobile phone, just like with a remote control.
1. Call 020-720 200 and follow the instructions to colour the tower. The call is free of charge and limited to five minutes. Click the "live" tab above to see a live view of the tower as you change colours. From outside Sweden, call +46 8 122 012 35 (please note that this number is not toll-free).
2. Select the floors you wish to colour by pressing the digits 0 to 9, 0 being the bottommost floor, and 9 the topmost. Finish by pressing #. At any time, you can press * to go back and change your selection of floors.
3. Colour the selected floors. Any colour can be created by mixing red, green and blue. The digits 1 to 3, the top row of numbers on your telephone, control red. 1 gives less red, and 3 gives more. The middle row controls green. 4 gives less green, and 6 more. The bottom row controls blue. 7 gives less blue, and 9 more. On certain telephones (e.g. Iphone), you may have to press several times to change the colour. When you have finished colouring, you can press * to go back and select other floors.