Document Builder is an application that merges multiple .docx files into one. In some cases, different people work on different parts of a document. The Document Builder app makes it easy to select multiple Word (.docx) files, change the order within a file, and merge them into a final document. Once imported, you just need to drag the files to reorder and use checkboxes to include or exclude them from the final document. This way, you save your time on creating similar documents by including only the necessary parts.