Poochy & Yoshi's Woolly World is a port of the Wii U platformer, Yoshi's Woolly World, for the Nintendo 3DS. In addition to all the levels of the original, this includes a new set of levels and new Poochy amiibo support.
The gameplay is mostly unchanged from the Wii U version besides the removal of multiplayer mode.
Aside from graphical changes (there's less detail like the ground depressing around Yoshi walking), there is a set of new levels and a new mode known as Poochy Dash. Players can get Poochy-pups to help players find secrets in the level. They will hop onto invisible clouds and areas of the level that can be moved into to get a secrets. Multiplayer has also been removed. There are also 30 unlockable shorts in this game. The player can also design their own Yarn Yoshi and share it via StreetPass.
The game was released alongside a brand new Yarn Poochy amiibo and is the only game to support it specifically. There are new amiibo skins for Yoshi like Callie and Isabelle. These were added to the Wii U version in an update around release.