FREE Knots 3D App (iOS or Android) Posted On January 3, 2020 Get the FREE Knots 3D App (iOS or Android) Reg. $4.99! Used by military, arborists, fishermen, firefighters, climbers and boy and girl scouts the world over, Knots 3D will quickly teach you how to tie even the most difficult knot. With more than 130 knots, Knots 3D will be your go-to reference! Grab some rope and have fun!Apple iTunes: FREE Knots 3D App Google Play: FREE Knots 3D App