I prefer to take notes and design code by hand. There are several good apps (Penultimate, Readability, Noteshelf, etc.), but they all seem to lack something I really wish they had: the ability to add space in the middle of the document, between lines.
Most or all of the handwriting apps I've used have a selection tool, but none of them allow you to insert text in the middle of the document.
As an example, imagine you've handwritten this list:
Oops: you forgot to write "Third." You tell the app to add space between Second and Fourth (which pushes the rest of the document down). Then you add it such that the list now looks like this:
Does anyone know of an app that affords this?