OmniGraffle

OmniGraffle is MacOS & iOS software to create graphics and visuals similar to Visio.

File Identification
OmniGraffle saves in an XML format with the extension .graffle. Files can also be saved using compression and may begin with. The root of the XML uses the "plist" DTD. Later versions could save a flat file or a MacOS Package containing the plist and other components.

Additional extensions related are .gtemplate and .gstencil.

Software

 * OmniGraffle downloads
 * LucidChart Graffle viewer