A Terms and Conditions agreement is the agreement that includes the terms, the rules and the guidelines of acceptable behavior, plus other useful sections, to which users must agree in order to use or access your website and mobile app.
It’s up to you to set the rules and guidelines that the user must agree to. You can think of your Terms and Conditions agreement as the legal agreement where you maintain your rights to exclude users from your app in the event that they abuse your app, and where you maintain your legal rights against potential app abusers, and so on.