The app keeps track of how many end posts, corner posts, sections, and line posts you have added. Once you are complete with a fence diagram, you can "save" it by clicking the save button. It will create an image of the diagram, and you will be able to email it to yourself, or a fence company for installation material requirements, or an estimation. This app does not take into account materials themselves, such as wood or vinyl, it just creates a diagram for you. You can decide the materials later. To use, you start by touching the screen , it will draw a line of 8 feet, and draw a post (a circle). Then you touch as close to the point in the direction you want the fence to go. It will draw another line in that direction. 

Click on the "end" button to end a line of fence. This is equivalent of digging an end post, and moving onto the next line.

Click the "Gate" button to enter a gate. This puts the program into "gate mode". The next line you draw will appear as a gate. (angled off to the side) . Gate mode will turn off automatically, so the next point you draw will be a section. 

Click the "Length" button to pick a section length from 3 to 10 feet. The default is 8 feet. This length is persistant, meaning it does not act like gate mode. Say you select 10 feet. All subsequent sections added will be 10 feet, until you change it to another length.

** sometimes you will draw a post unintentionally. As of now, I have not been able to create working undo button, but It should be ready in the next edition. For now, you will have to leave the mistake in, and explain in the email, or hit clear, and start over. My apologies for this inconvenience. Another issue is the zoom. You can zoom in and out, but the touch coordinates will be messed up once you do so, in relation to the fence points. I left zoom in there because if you have a large fence that goes off the screen, to get a good picture of it, you will have to zoom out (pinch and zoom). But don't try to zoom in and out while you are plotting the diagram. When you get close to an end, the diagram will shift over, so you can add posts without zooming all the way out. I will try to make zoom work correctly for the next edition. Another thing I am going to add is a grid overlay, to make it look like graph paper. I published it as is for now, because I feel it is usable enough. I will continue to fix these issues as soon as possible