For [[SYSCLS_EDITABLEDOCUMENT|editable documents]], there is an {{key press|edit}} button in the top app bar. It allows the user to edit a document file using the default app of the OS. If a file is changed during the edit, the same {{key press|save}} button appears just like it does for content with changed properties.
{{Hint|Similar to saving, other app features also apply on edited documents. For example, reverting local changes for an edited document will throw away the changed document file and restore it to the server version.}}
An alternative way to start editing is to right click on a document's thumbnail or clicking on the "open external" button inside of the document viewer, which immediately opens the document in an external editor (WinX). To open the document externally in order to start editing on the mobile client you have to use the left-swipe functionality on the document object. The difference here is that there is no {{key press|save}} button and any changes are automatically saved (and committed if in online mode).
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File:EditingMAUI.jpeg|Open external button Mobile ClientFile:DocumentViewerButton_WinX.png|Open external button on WinX Client
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