Build a App that can Quote,Draw Basic Shapes with measurements and invoice

I own a Concrete Pool Building business and i want to have a App tailored to my company ONLY! It will not be fore sale. When i go and Quote a Pool at someones house I would like to drawon my ipad a basic picture(attached), i am Currently Using Quotientapp for my quoting and a piece of paper for the rough sketch. It would have to be on my Ipad or Iphone or Android phone or tablet I guess its similar to a spread sheet that calculates Quantities and amounts with pictures for each item with a description of that item. Potentially wanting to add a invoicing section to the app/program like quick books or Zero but a basic version Both Screen Shot are of the current Quotient i am using to give you an idea on what i am wanting. The last file attached is of a drawing i would like to be able to draw( simple squares and rectangles) with lines and measurements in millimeters and a key below that i can customize i am happy to draw up a click chart on how i would like it set up. Please visit my website to get an idea on what style and simplicity i like [login to view URL]