The postpaid mobile phone is a mobile phone for which service is provided by a prior arrangement with a mobile network operator. The user in this situation is billed after the fact according to their use of mobile services at the end of each month. Typically, the customer's contract specifies a limit or "allowance" of minutes, text messages etc., and the customer will be billed at a flat rate for any usage equal to or less than that allowance. Any usage above that limit incurs extra charges. Theoretically, a user in this situation has no limit on use of mobile services and, as a consequence, unlimited credit. This service is better for people with a secured income.