Before you can use Facebook Mobile, you have to do a little bit of easy setup. You just need to activate your phone number, and then adjust your mobile settings; the following sections show you how.
Although Facebook Mobile is a Facebook application, you don't install it the way you do other Facebook applications (Facebook Applications: An Overview). Instead, you have to follow the activation process explained in the next section. After that, Facebook lists Facebook Mobile in your Applications menu.
Activating your phone means associating a cellphone number with your Facebook account, and then testing the connection between your phone and Facebook. To activate your phone:
At the top right of any Facebook screen, click the "account" link. Then, on the page that appears, click the Mobile tab.
On the Mobile tab, type your cellphone number into the Phone Number field. Include your country and area code, but leave out the punctuation, like dashes and parentheses.
From the Carrier drop-down list, choose your cellphone company, and then click the Activate button. Facebook redisplays the Mobile tab, complete with a message letting you know you'll receive a confirmation code on your phone shortly.
Check your cellphone. It may take a few minutes for the text message with your confirmation code to arrive. If you don't get a text message ...