Furigana on AnkiDroid

I’m using AnkiDroid on my smartphone and wanted to add furigana to my flashcards. Until now I just found threads were they talk about Anki for the desktop but not about AnkiDroid.

The format should be

(space)Kanji[furigana]

It works on AnkiDroid by default without requiring Japanese Support.

Why the space?

Thanks for your help. Still seems to have trouble saving the note. When I try to save it an error message pops up.
You can see my setup below.