With all due respect to the previous commenter who had a special application, this is a horrible photo frame. It has (at least) two huge problems:
1) The picture quality is horrible. It does not look like a photo displayed on your laptop -- it has garish colors and highly visible contour lines in what should be smooth color gradations. It looks like an 8-bit image you might have seen in the 80's or 90's, and I would not be a bit surprised to find that the display only has 8 bits of color resolution.
(BTW, I do not fault the 800x600 pixel resolution, which is mediocre but adequate for a product of this class.)
2) Photo slide shows can only be displayed at three intervals: 3 sec, 5 sec, and 10 sec.
I have a nice Sony photo frame that I keep rotating family pictures with an interval of an hour. It's like a regular photo that happens to change now and again. A ten second slide show, on the other hand, is an active and intrusive piece of media that demands your attention and draws your eyes involuntarily towards it. Sure, there are uses for 10 second slide shows, but I do not want one in my living room. This seems to reflect a complete failure of imagination about how real people might want to use such a product.