One of the best ways to design a software system is to capture the business domain, its users, and their interaction with the system as a user story (https://en.wikipedia.org/wiki/User_story). User stories are an informal way of capturing the requirements of a software system. In user stories, the focus is on the end users and the interactions that are possible between the users and the system.
The first step in writing user stories for the Helping Hands application is to understand the users and entities of the system. Primarily, there are two users of the system—Service Consumers and Service Providers, as shown in the following diagram. Service Consumers subscribe to one or more services provided by the Service Providers. The core entity of the application is the service. A service is an intangible, temporal, and limited asset that providers own and provide to the consumers on-demand at a price.
Service Providers register one or more services with the system that...