Looks nice, on my iPhone (and maybe my iPad too?) I don't hear a voice at all.

Neat!

Jerry Pournelle often mentioned having an application which would teach reading --- apparently it is now out of print?

https://www.readingtlc.com/

Have you looked at intermediary things such as the "Living Books"?

https://wanderfulstorybooks.com/

Neat project. Too bad it only handles English phonemes, as it would be very valuable for teaching other languages. Maybe someday I'll convert it from ARPABET to IPA...

[dead]