On his island, Fyer offers strange cannon rides for a small fee; one shot out of Fyer's cannon has enough power to launch Link up to the bridge over the lake—an invaluable resource when Link has been changed back into human form with no way to warp to higher ground. Fyer, eventually, along with the badgering of Auru, an old friend of Fyer's, allows Link to experience the "Oasis Flight", which is a cannon ride that launches Link from the lake into the Gerudo Desert. Talking to Fyer after talking to Auru is the only way to further the quest to the Arbiter's Grounds, a sacred dungeon deep within the Gerudo territory.
In the end credits, Falbi and Fyer appear to be hovering over Lake Hylia with chickens, most likely from Flight by Fowl.
Fyer has an image of a Bullet Bill on his right (left in the Wii version) sleeve.
Fyer's name is likely a pun on "fire", referencing his profession in cannon-work.
Early concept art found in Hyrule Historia shows Falbi was originally intended to be female. Fyer was to be either Falbi's husband or her lover.
Concept art of Fyer
↑"In the concept art shown here, Fyer is male, as he is in his final design. Falbi, however, is female. It is unclear if they were meant to be lovers or husand and wife." (Hyrule Historia (Dark Horse Books), pg. 186)