I have already written in my portfolio that my first book on Apple Books was approved. The book is for free, but it’s in the Russian Language. However, Apple allows publishing books only in 51 countries in the world, Google in 66, and Amazon only in 10-20 countries. In other countries available public domain books only or only preview.
I don’t know why, but Apple, Google, and Amazon are loose money with this approach. In addition, it’s extremely not convenient to use their apps for users.
For example, as I said above, in most countries available public domain books only. Therefore Russian and all former USSR citizens will not be able to download my book, even it’s for free. Only Russian-speaking who are living in one of these 51 countries (66 for Google Books and 10-20 for Amazon Books) can read this book. Even I can’t open my book through Book app despite the fact that I’m using the Taiwanese App Store. Because Taiwan also isn’t one of these numbers of countries.
I think, even if Apple, Google, and Amazon will allow publishing in all countries in the world, then they are already too late, because they’re not the ones in the world who can distribute digital books. I know at least the three biggest Russian online book stores. They have a lot of offers, discounts, bonuses. I’m sure other countries are the same and they already have their own very good Apple Books, Google Books, and Amazon Books alternatives.