This app is an application that instantly lists Yojijukugo including that character (reading) from only one character (it can be either "reading" or "kanji").
As a search method, you can search by "forward match", "partial match" or "backward match".
For example, if you have a Yojijukugo that you have remembered ambiguously, you will be able to find it right away just by entering the single character you remember.
Also, for example, if you happen to be surprised at the moment and you want to express it in Yojijukugo, searching with kanji "驚" might mean you to first know the Yojijukugo word "驚天動地" not.
Perhaps, for writers and bloggers who are supposed to be writing documents, there may be interesting findings of Yojijukugo.

The four-character idiomized words (Yojijukugo) listed can be managed as "favorite" by putting a check in the heart mark.
You can also check the meaning by tapping on the Yojijukugo listed, and it is managed as "history".
If you tap long, you can copy that Yojijukugo to the clipboard.