Cast your line and get back to work. When a fish bites you'll hear a splash and the tab title blinks, and with alerts on you'll get a notification too. Come back and press once to reel it in.
Collect 66 species at the riverside, reservoir, lake, breakwater, rocky shore and on a boat. See How to play for details, the Fish log for the fish themselves, and the Fishing guides for real-world fishing tips.