Application in two languages ​​do 1 or 2?

Question

Android

I'm making a children's book in Russian and I didn't want to translate it into English. I don't know how best to make one version with a choice of language or make separate Russian and English versions?

Answer 1

Promotion point of view is better one

Answer 2

And with logic too.

Answer 3

And plug the audio versions of both languages ​​into it with some kind of player, and synchronize with the text so that you can, for example, listen in English and read in Russian at the same time, like subtitles.