The ratio of mobile phone users in Thailand. Compared with the population of 100 people found that most people use mobile phones in Thailand up to 123.44%. The average population of one person using a mobile phone 1.2 number. Reflect that population almost everyone has a mobile phone number except for the baby. And mobile phone users, more than one number. Therefore, service providers, both old and new to be done is to convince customers to use the mobile phone network as much as possible. Which requires all marketing strategies to retain customers.