How do I delete?
Deleting is one of the most basic functions of any application, and should be as simple and intuitive as possible. To delete any object, just double tab on it or it's handle. This may not seem intuitive until you've used it - after which you may wonder why other apps don't have this feature.
Note concerning the Sketch Mode - Line Straightening Feature
The line straightening feature in the "Sketch" mode uses a very complex algorithm to straighten lines, close gaps and snap to the grid. While this feature can be extremely useful for doing quick sketches, it is totally inadequate for doing most dimensional drawings. In addition, when used to excess this feature can cause the App to dramatically slow down and eventually crash. I therefore, strongly recommend users do most of the detailed work in the "Lines" mode.