Some may or may not know Navionic's sells a phone app for about $10.00. This is like having a handheld gps, showing you every detail of the water way your on. From channel lanes contour lines bouys, docks all the water way info one needs.
This is a $150 chip for your depth finder, the go to product used by millions of fisherman both pro/sport.
Great insurance if you ever lose your depth finder. All depended on a cell signal.