Methods, servers and systems for directly accessing and modifying charging information maintained within a telecommunications operator's business and operating systems' infrastructure from user equipment. A mobile application server may receive a charging request from a user equipment, identify a relevant charging system based on the received request, send a charging request to the identified charging system for processing, receive a first response message including charging information from the identified charging system, generate a second response message based on the charging information included in the first response message, and send the generated second response message to the user equipment. The received charging request may include various types of information, including information for transferring cost or billing information from a first billing category to a second billing category.