"Fill and Cross. Pirate Riddles" is a program for Mac that provides you with dozens of challenging nonograms. This game is suitable for users of all ages, gives you access to a thorough help guide, offers you numerous hours of gameplay, and may become very addictive if you're into the aforementioned type of puzzle.
After you create a player profile (you can create multiple profiles if necessary) and start the first mission, the app brings you various gameplay instructions. You can disable these hints if you don't require assistance in completing the levels.
Also, if you're new to this type of puzzle (nonogram) you can use the integrated help guide that explains you how to complete challenges. Your goal is to reveal an image hidden on the board by clicking over the tiles while following the column and line instructions. As you advance, the difficulty level increases and the column and line numbers get bigger.
To be honest, one of the reasons I enjoyed playing this game is that it doesn't give you access to tile hints and it restricts you to making a maximum of two mistakes per level. This way, the missions get even more challenging than they already are.
All in all, I'm a big fan of nonogram games and I definitely recommend you try "Fill and Cross. Pirate Riddles" as well.