I would like to hire an App Developer

Simple Interface Android Application. We sell cow/buffalo milk in loose quantities via servants. So I need an android application with an admin, customer and employee logins. Employee Login: Select a customer account from a drop-down, add the quantity of milk purchased and the amount paid, which gets frozen once it is submitted by him and an auto-generated text message sent to the customer with the quantity of milk purchased and payment made with time and date. All this is stored in a database with the timestamp. Another option if a new customer not in the dropdown makes a purchase. Customer Login: He/she can see the list of the quantity of milk bought and payments made and total quantity within the start and end dates which he/she can select from the calendar. Admin login: 1. Option to check the quantity of milk sold by each employee each day. 2. Option to add/edit/delete customer accounts(Name, Address, Contact Details, Employee Serving) and allocating these to employees. These customers will appear in the dropdown of the employee allocated. 3. Access to the database so that can be extracted in the form of excel sheets. 4. Access to any customer account to edit if there is any mistake made by any employee while entering data. 5. (Only if it's not too much work) Track the location of each employee on the google map.