Thank you for the quick answer.
It's even weirder: the photo's are saved at the tablet, however: I just got an empty picture (only a border without any graphical info.
Unfortunately I deleted all those "empty" pictures, but I'll make some new ones,
and send you some.
MAy take a day or so, other ...

I do use a NIKON D5000 and a Samsung Galaxy S3 tablet.

I installed Helicon Remote, and all seems to work. The camera is recognised, all settings can be changed, preview works, and taking a picture seems to work.

However, no picture is saved, neither on the camera's SD-card or on the tablet.

How ...