The present research is part of the project called PHUKUY, which is a low-cost portable digital spirometer prototype designed for remote monitoring of patients with COPD and COVID-19. It also includes additional sensors for improved patient monitoring. This article presents the development of the spirometry module. A turbine spirometer was chosen for its small and lightweight size, easy cleaning and maintenance, and low-cost implementation, which allows for portability. The airflow was successfully digitized, and its direction was detected using a microcontroller, a pair of IR receivers and emitters. This information was then sent via Bluetooth to be displayed in real-Time on a mobile phone. For a 3-liter calibration, a maximum error of ±0.115 liters and a standard deviation of 0.051 were achieved.