Hands-down the best introduction to Picross puzzle solving you can get on the App Store right now, and even old hands should find something to entertain them. A superb puzzle game by anyone's standards.
Help! Repaint missing works of art such as “Surfing Elephants,” “Deer Taking the Alligator Ferry,” and “On the Day of the Apocalypse, Treat Yourself to a Popsicle.” This whimsical puzzler is a gem for all ages.
Ultimately, Paint It Back is a traditional, brain-teasing puzzler that most people can enjoy. It’s simple enough that even children can figure it out on the lowest levels, but can be varied and expanded upon to the point where you need a genius to solve it.