Using the iPad and iPhone app, you can open files in your Egnyte account - Word, Excel and PowerPoint files (or their Apple equivalent) in Apple's iWorks apps. For example, you can open a PowerPoint in Keynote via the Open with function. If you make changes in Keynote, you can push it back into your Egnyte account using the Copy to WebDAV functionality in Keynote.
You can configure your webdav access in Keynote (or Pages or Numbers), by setting the following:
Server Address: https://mycompany.egnyte.com/webdav
User Name: <<your Egnyte username>>
Password: <<your Egnyte password>>
iWorks file (i.e. Keynote, Pages and Numbers) can be saved as a single file or as a package. If you save the file as a package, then it will be uploaded as a zip file or as a folder on Egnyte.
Apple suggests that you save the files as a single file if you plan to upload them to a non-iCloud Internet Service.
Please refer to this Apple KB article for more information.