Knot Guide (iOS: $1.99)

Spend any amount of time fishing and you’re going end up tying knots. Lots of knots. Even if you haven’t earned a knot-tying merit badge, fear not: mobile apps like Knot Guide come to the rescue. The Knot Guide iOS app provides users with detailed information about more than 100 knots, divided into 18 categories, including binding, climbing and sailing knots, and most relevantly for us, fishing knots. Users can explore knots by name or category, and each entry comes with a description of its uses, as well as a visual guide to tying the knot. Users can save their favorite knots, as well as read up on knot-tying lingo, as well as share their knot-tying work with other users.