Documents are files that can be attached to client or subcontractor. Their file format can be of any type. The purpose of attaching of these files to clients or subcontractors is to open them for view in pdf, mp3, images or text files or to attach and send them with invoice or receipt. In any case, you will have them on your device for check up. For example, you can attach pdf files of construction design, plan or outline to a Client and check on your mobile device if construction work is going according to plan.