Compared to earlier Touch HD's, 3 adds BT, waterproofing, and upgrades internal storage to 16 GB. At the same time, it removes the SD card slot and 3,5 mm headphone jack.
https://www.pocketbook-int.com/de/ne...n-im-e-reading (announcement in German)
Specs
https://www.pocketbook-int.com/de/pr...specifications
Edit: Demonstration
https://www.youtube.com/watch?v=P5_fJL9ouNA