Handwashing is a basic infection control practice that needs to be performed correctly to be effective. In the ongoing COVID-19 pandemic, its correct practice is emphasized by public health institutions. However, turning a practice into a habit requires acceptance for adoption of the twenty-second proper procedure to which difficulty remains. To promote and convince the average user, we developed the “APD Handwash app” as a home-use demonstration/education tool to the pitfalls and need of proper handwashing practices through the detection of assigned clean or dirty areas on the hand in a quantitative manner to provide a gauge to the effectiveness of washing when used before and after washing.