Ink is a relaxing adult coloring book app that allows you to create your own art by filling in illustrations with the numbers and colors you choose. 

The app has a simple design and the interface is intuitive. The number of colors to choose from and the way you can paint each area make it a fun and creative experience. 

There are various categories of illustrations for all skill levels. Choose from beginners, simple, and more advanced designs and create art that is unique and personal. You can choose to color only certain areas of a design. 

Ink allows you to save your art and share it with others.