If your mobile phone belongs to Sony Ericson K series, you should try this out .

1. First move navigeringstast button into right side once. After that press button which has “*” symbol .
2. Then again move navigeringstast button into left side twice and press that button (“*”) .
3. After that move navigeringstast button again into left side once and press that button (“*”) .

Once you did above three steps, you will see three statements on your phone screen. Click on that each statement and see what you can know about your phone.

Note : try this with other Sony Ericson serise as well