At the moment, there are about 27 images to solve. The photos themselves are quite nice. I solved them all.
Ozaiko is perfect for that person who is a casual puzzler. As for me, I'm in the middle of doing some very serious puzzle apps which require lots of concentration. Playing Ozaiko was a nice break.
Update 12/8/15: Ivan contacted me and figured out that I never saw the menu on the right side of his game! I did all the puzzles using the smallest number of slices. These can be increased to 18 pieces per ring! Obviously, more challenging.