USB otg auto sync

[rien-ne-va-plus]

Hi guys,

I hope you can help me because I'm starting to feel stupid.

The task at hand seems easy. I want my phone to automatically sync certain folders to the USB otg device when it is connected. Similarly to what many apps do with cloud storage. But I have not been able to find a tool that does that. Can anyone help?

Thanks and cheers,
rien