How to Download Documents in a SharePoint Document Library or Folder

To enable Offline Sync at a SharePoint document library or list level:
1. Tap a SharePoint site
2. Tap “Offline Sync” button for a document library that you would like to enable the offline sync
3. Tap Save
4. Tap the “Start Sync” in the upper right corner

To enable Offline Sync at a folder level:
1. Navigate to a document library
2. Perform long-press (hold and press) on a folder of a document library
3. Tap “Offline Sync” button for a document library that you would like to enable the offline sync
4. Tap Save
5. Tap the “Start Sync” in the upper right corner

Please note that, if you want to perform offline sync using a cellular data such as 4G LTE or 3G, please go to Settings, and then disable “Sync on 3G /4G LTE.”

Also, please note that, to enable the offline sync at a folder level, there should be no offline sync at its document library. Please disable the offline sync at a document library level to enable the offline sync at a folder level.