Has it been a long time between visits to your local fishing hole? Besides the increased costs for a fishing license, a permit, and launching/renting a boat, you may also realize (like I recently had) that you need a refresher on how to tie a knot and not just any knot, but the various kinds necessary for fishing, such as the Figure 8, Surgeon’s Loop, and Trilene Knot. All these and more are found in this app, Knot Time, with concise detail and supported by video. Other covered categories include Boating, Mountaineering, and Lashings. Useful and cheap. Price: 99¢.