Android/iOS: This tab is not available in the Android and iOS versions. However, simple backups can be made here. This setting can be found on the Files tab.
On the Backup tab in the dialog box of the ribbon command File | Options 
, you can make settings for creating backup copies:
"When you save a file manually..." section
▪Keep older versions of the document (if you save a file manually)
| Several generations of file backups are created for each document. All of these copies are stored in a special Backup folder. |
Tip: If this option is enabled, the command File | Versions  (in the group File management) is also available, which allows you to easily return to a previous file version of the currently open document. |
▪Number of versions to keep
| Here, you specify the maximum number of backups (generations) to be kept per document. |
"Automatically created file versions (snapshots)" section
▪Save unsaved changes every ... minutes
| If you want automatic "snapshots" to be created as an additional backup while the document is being edited, enable the checkbox here. In the dropdown field to the right, you specify the interval at which the snapshots are to be taken regularly. |
▪Number of snapshots to keep
| In this dropdown field, you specify the maximum number of snapshots you want to keep. |
Folder for file versions
Here, you can change the path for the Backup folder in which all backups are stored.
"Clean up" button
This button provides two options for deleting file backups from the backup folder:
▪Delete orphaned file versions
| This option removes all Presentations backups for which the corresponding original document no longer exists. |
▪Delete file versions of all documents
| This option removes all backups from Presentations. |
For more information on using file backups, see Backup copies (file versions).