I'm fully blind and I use VoiceOver, Talkback, and Voice Assistant for my job, but am very much primarily a VoiceOver user with my iPhone SE. 80-90 percent of blind users in a WebAim survey use iOS and VoiceOver. I prefer it because it's smoother, not as clunky or as buggy as Talkback, feels much more designed rather than just engineered, has braille screen input and live screen OCR with media descriptions when encountering pictures in apps, and the voice synthesis options are much clearer and more pleasant than the Android voices.

The only issues I have with VoiceOver is when apps aren't designed correctly or don't take accessibility into account, making it impossible to use a screen reader with the app. It's easier for iOS developers to tweak code and make elements accessible compared to fixing issues in Android, so updates are more frequent and developers tend to be a little more responsive on the iOS side.

I'm only visually impaired but I do use screen readers quite frequently. I use both iOS & Android but prefer the voice synthesis (I think it also uses some form of sampling/recording) of Android.

https://deepmind.com/blog/wavenet-generative-model-raw-audio/

https://venturebeat.com/2018/09/27/voysis-develops-offline-wavenet-voice-recognition-model-for-mobile-devices/

i have achromatopsia, which makes me legally blind. for the most part, i can use smartphones easily, but small text/graphics and low contrast are difficult for me to see, so some apps and websites aren't accessible to me.
(im mostly counted as legally blind due to the fact that sunlight makes me almost blind. inside, my vision is bad only at distances, but this bad distance vision can't be corrected by glasses since its cause is different than most near-sightedness.)