CRM apps in flutter or react

Please don't send me bid if you don't have explmaes of simailar apps that you can show me that doing the same functionaitly like CRM app or something like that. Building an application for customer management Requirements: The Admin is required to have the following capabilities: 1. Establishing customers Correspondence with customers Sending messages to customers. Scheduling appointments with the client, sending a reminder to the client before the appointment date. 4. Viewing the customer file Ability to add documents to the customer. 5. Assign tasks to the customer and see if the customer has performed them. 6. Ability to view the customer's sales status graph (by month and by week). The customer is required to update each week how many sales he had each week and the graph should be displayed to the customer and also to the manager. In case the client is given a mistake both the manager and the client can edit the graph. 7. Conduct notes or meeting summaries regarding each and every client. 8. Ability to manage customers delete and block customers A customer should have the following capabilities: 1. Can correspond to the manager 2. View tasks he has been given, update a task and change its status and make notes about the task. 3. Upload documents. 4. Confirm arrival at the meeting or postpone and request re-coordination of the meeting. 5. Update how many sales he had that week. And see the graph of sales he had on a weekly and monthly level. 6. See a history of the meetings he had. 7. Sign up for the app (username, password, phone and email, or login with Google),