The number to which answers must be sent depends on the country you have selected in your account settings.
You can display that number by starting the "How to participate?" question, or by clicking the i button when displaying a question.
You can change the number to a different country's in your Account settings (which are accessible by clicking on your username in the top right hand corner).
We currently have a phone number for the following countries:
Note that the text messages will be sent at the normal rate with no additional charges. The American/Canadian number are toll-free, even without a phone contract.
Don't hesitate to contact us if you want to participate via text message in another country.