It might not seem like much, but Google Play Books just updated with built in TTS. It’s a bit robot-y for now, but as TTS improves, this could really turn into one of the most useful features for the app.
If every single text book can be a native TTS book, that’ll be awesome. I don’t know if you’ve seen the prices of audiobooks, but they’re up there.
I also think it’s the same voice they use for navigation, which itself was improved a few years back from the old Navigation voice.