Dynamite Fishing is a "redneck" sport, and this is the game version. The idea is simple: you have some dynamite and you have limited time to get a good haul of fish. You can also shoot a few birds. Later, you can buy access to other lakes, more weapons, and more.
The game looks to be a bit deeper than at first look. You start in the most basic boat (actually, it's a bathtub). Later you can upgrade to a... battleship? (What's what for? The Loch Ness Monster?) the idea is use the minimal amount of ammo in the minimal amount of time for the maximum results. You can tilt left/right o move, then tap to release the dynamite. Clearly, some stuff you should not hit, and others takes multiple hits.
As it was free for a day on Amazon Appstore, it's worth a try. Otherwise, try the demo.