Custom Drupal Module

I need a custom Drupal 7 module that will allow me to edit some settings that are used by iOS, Android, and BB apps. What I am looking for is very, very similar to "Date and Time" in Drupal 7 Admin Regional settings. I have provided a PDF with the desired layout. I have also attached a PHP file with all the settings that I need. It includes section name, field name, display name, field type, and default value. Let me know if this information should be provided in a different format. The module should also allow me to pass information to a url and view the information as a JSON file. It will look for the configuration matching the platform, app version, and debug flag and return the appropriate configuration. For example: [login to view URL] should give me a JSON file with the settings for iPhone platform with app version 3.1 and debug is false. I have attached an example of what the output would look like. Currently I am managing this information with a custom PHP form in two steps and I would like to integrate it into Drupal so that I can manage settings and content together.