Here's the way Ridiculous Fishing works: you, playing as Billy the Fisherman, cast your lure. On the way down, you avoid fish for as long as you can by tilting your device, to the strains of a jaunty 8-bit soundtrack. After you strike a fish, you rise back up, and catch as many fish as you can, by tilting your device. And once the fish break the waterline, you shoot them to death, by tapping your device.
Within fifteen minutes of playing, you are armed with an Uzi, a lure/chainsaw hybrid, and thousands and thousands of dollars from selling your haul. It's PETA-bait (we'll see if they BITE. I'm so sorry.), it's a visual delight, and it's the most fun I've had with a mobile game this year. Play it.