It is an application only for checking with the character conversion function of the mobile when you forgot kanji.
When I forgot kanji, I think that everyone has confirmed using a cell phone. What was the app launched at that time? Is it an email app? Is it a browser?
Even if you don't start such a heavy app, you can quickly check the forgotten kanji with "light forgetting" if it is "forgettable kanji".
It also supports voice input for those who are troubled with character input.

As it is simple design of only character input column, voice recognition (it is function of Android), input character clear button
When you say, "How do you write that kanji?"