A slightly techie solution to what I think you are trying to achieve (?)...... 
For Android/PC/Mac I have used Dropbox / Dropsync to keep them in-sync.
Simply a case of syncing the \sdcard\Skydemon\ directory on the Android with c:\users\<username>\documents\SkyDemon\ on the PC.

This involves a little bit of extra syncing on the PC (between the Dropbox folder and the Skydemon folder) as SkyDemon doesn't appear to allow you to configure where it keeps it's stuff and won't work with a junction point, but on the Mac / Android it's all straight forward.

Perhaps if SkyDemon allowed you to configure where the SkyDemon data directory/folder was located, then people could use (or not use) their cloud storage synchronisation provider of choice..... albeit that doesn't solve for iPad.