Add the support to display furigana.
It is rather simple.
If your text display software sees japanese/chinese text like '見', dont do anything. If it sees the text like this '見(み)' add the stuff in the brackets above the character, such that the end of the string in the brackets lines up with where the brackets would have started. Furigana typically is displayed at 1/2 or 2/3 to 3/5-ish of the original font size above the corresponding text. You obviously need to code in half an empty line so that the furigana does not overlap with the preceding lines.
This only applies to the lyrics/synced lyrics part of your app.
About what the hell i am talking about: Furigana - Wikipedia: https://en.m.wikipedia.org/wiki/Furigana
Kind regards,