A:With no videos or photos, Knots 3D is definitely not the most user-friendly app reviewed here. However, the designers have put a real effort into modeling each knot in 3D. With Knots 3D, you can run your finger across the screen to scrub forward and back on animations, and read well-written descriptions of each entry. Sections describe the reliability of each knot, and even give an account of its history.
NUMBER OF KNOTS: 87
Android, iPhone, and iPad ($1.99)