Yo-kai Watch 4++ Connect App is a mobile tool app developed by LEVEL-5 Inc. Users can connect this app to the PS4 game Yo-kai Watch 4++ to read different datas and get special items.
Yokai Watch 4, 10 minutes off-screen gameplay
WIP] Yo-kai Watch 4 ++ Switch English Translation Project
Yokai Quest Strikes Back by Zenitminiatures — Kickstarter
WIP] Yo-kai Watch 4 ++ Switch English Translation Project, Page 7
Yo-kai Watch 4 lets you switch between humans and yo-kai in battle - Gematsu
Connect, pop and collect the yokai in Yo-Kai Watch Wibble Wobble
Yo-Kai Watch (for Nintendo 3DS) Review
Connect, pop and collect the yokai in Yo-Kai Watch Wibble Wobble
Yo-Kai Watch 4 (2019), Switch Game