"If you’re fishing in a boat, you can use technology to help you find where the fish are hiding, such as the fish finder systems you have probably seen mounted near the steering wheel of many boats that are cruising the lake.
If you’re fishing from the shore, you don’t have access to that sort of technology. A new project on Indiegogo right now called ReelSonar is a fish finding device that works in conjunction with your iPhone to help you find the fish from the shore or from a boat. The device is a fancy smart bobber that has sonar technology inside."
Via Mo Hall