After the $9.99 Shadow Raps that finally helped my buddies and me dial in on stubborn bass early this past Spring, my next best tackle purchase is a mobile app - "Knots 3D".
If I only used "Knots 3D" to correctly tie the Uni-to-Uni knot I use for my 12lbs flo leader to Sufix braid, the app would be we'll worth the $2.99. However, it demonstrates every knot I'll ever need in 3D animation that's completely controllable.
What has been your most helpful tackle purchase in 2015?