You can use it in Dodongo's Cavern, in the first hallway you explored as a kid. There's a niche up on the left in an area between the sets of baby Dodongo attacks. There's a gold skulltula spider up there (one of two that only Adult Link can reach). In the Shadow Temple are two more places to use it. Before playing Zelda's Lullaby on the ship, you can reach the Recovery Hearts up high near another gold spider. You need the Longshot, even if all you want is the spider token (but you don't need the scarecrow just for that). Later, after you cross the toppled statue, more Recovery Hearts can be reached with Pierre after creating a Time Block to stand on first. There's also a place in the Statue Room of the Gerudo Training Ground, if you want to waste your time getting the useless Ice Arrow.