Aplicación móvil para la automatización de la facturación electrónica y gestión de ventas físicas de gas licuado de petróleo para el distribuidor Duragas en el cantón Urdaneta, provincia de Los Ríos.

Abstract

Duragas, a liquefied petroleum gas (LPG) distributor located in Urdaneta canton, Los Ríos province, served its customers through paper-based invoicing, a slow process prone to data-entry errors that did not comply with the regulations of Ecuador's Internal Revenue Service (SRI) regarding the issuance of electronic receipts. In addition, cylinder inventory was managed manually in notebooks, causing unexpected stockouts and financial losses. To address this problem, FactuGas was developed, an Android mobile application that automates electronic invoice issuance and the management of the physical LPG cylinder inventory. The system was built in Kotlin under the MVVM architectural pattern, with a Laravel 12 backend deployed on a Debian 12 server with a PostgreSQL 16 database. Digital signing of receipts was implemented under the XAdES-BES standard, and communication with SRI's web services was carried out through SOAP, in compliance with Resolution NACDGERCGC18-00000233. Development followed a hybrid Kanban and Extreme Programming methodology, suited to a single-developer context. The system allows the Cashier, Warehouse, and Administrator roles to operate according to their specific functions, and was validated through unit, integration, acceptance, and regression testing, including a closure test in a real production environment. As a result, a functional Android application, a production backend, and a web administration panel were obtained, which reduce customer service times and ensure the business's tax compliance.