The Terms and Conditions agreement can act as a legal contract between you, the mobile app owner or developer, and the users of your app. Like a Terms and Conditions for a website, this agreement for a mobile app would set the rules and terms that users must follow in order to use your app.
A Terms and Conditions could legally protect your ecommerce store. It is in this type of legal agreement where you set the rules that your customers would follow during a purchase and limit your liability in the event that your products fail.
There are multiple reasons why SaaS businesses would want to have a Terms and Conditions as a legally binding agreement between the company and the customers accessing and using the app on a regular basis.
Think of the Terms and Conditions as a legal contract that the SaaS company and its customers are signing together: the terms and rules as set in the agreement will govern the access to the app.