Need a Basic Android App

Main purpose of this app is taking order from customers. There must be 3 screens in this app. First one as in the picture is log in section. This is very simple log in. I only type my name as a text. no need for database. this name will show up in the excel file which will be created in main screen. After log in Main screen show up. In this screen (as in picture.) First there are 2 options (this indicate 2 different brand). And there is a cell for search and choose downlist ( while i start to type, there must be downlist for most fitted names) ( those names will come from a excel database file, i should be editting this database easily to add more customer infos) After customer part, there is order part. As you see in the picture, there are 3 columns. First is a downlist for product codes ( as customer name cell, this should be come from a excel file too). Second columns for only numbers ( piece of products). Third Column is for product details ( A textbox for any text) . Lines can be added auto when last line is filled. After typing is done, there must be a save button. When you save, it should save as a excel file.( Excel file name also should contain the customer name, the brand name which chosen, and the user name which wrote in the first screen. And there is third screen. as in the picture. This screen is for editing, deleting, and inspecting orders which saved in the main screen. (Ofcourse those are excel files saved to a server)