This project aims to design and develop a centralized back-office management application for freelancers, capable of seamlessly integrating with popular communication channels such as LINE and Facebook. The proposed system includes key features such as generating quotations and invoices, managing schedules with automated reminders, tracking income and expenses along with work history statistics, supporting multiple accounts (e.g., multiple Facebook Pages and LINE Official Accounts), and providing a unified chat inbox to consolidate messages from various platforms.