On-demand apps are applications in our devices commonly known as mobile applications that help to make our lives easier by offering us instant access to our day-to-day services. They range from applications such as online food delivery apps to ride-sharing applications, applications that help in finding the nearest plumber or any other service provider, and even telemedicine apps that help connect clients in need of medical advice with relevant professionals. Making mobile apps that allow on-demand access to services means adding convenient user interfaces and ensuring that payment for services is safe and easy.