Outside my Kindle Fire tablets, I'm more of a Gelegenheitspuzzler, especially since most puzzles me take too long with their 500 (+ -) parts. This app provides entertaining puzzle fun in between - in the free version several motifs are included and I can choose at each new round, as many parts are to be it. Whether 4 or 169 - the truth usually lies somewhere in between ;-)
Additionally, you can choose whether the puzzle pieces should also be rotated during mixing and there are three stampings for the puzzle pieces to choose from.
At least the "Puzzle of the Day", which changes daily, I take always happy with :-)