Convert excel spreadsheet to iPad app for remote data capture

Hi, I am looking to create a simple iPad app that can help our field reps to calculate margin (POR) I currently have a simple, straight forward Excel spreadsheet that we entered the sales price, cost price, account discount, VAT and POR required, etc into. I want to convert this excel spreadsheet calculator to simple iPad app. It needs to function offline all the time and no need for an Internet connection. Excel spreadsheet requires inputs and performs a calculation and creates a selling price and POR Skills required: Excel, iPad