Android Lollipop (5.x), Marshmallow (6.0) or Nougat (7.x)
If you are using Lollipop (5.x), Marshmallow (6.0) or Nougat (7.x) then SyncBack Touch can be configured to write to external SD cards.
Android KitKat (V4.4)
When using SyncBack Touch on a device running Android KitKat you may encounter the following error while trying to copy file into the device's external SD card with SyncBackPro/SE:
Permission denied (EFCreateError)
This is a known security feature where Android sandboxes applications when it comes to writing into external SD cards. Applications can no longer write wherever they like into external SD cards, causing issues similar to this one.