Would it be possible to add the option of hiding pinyin while doing reading prompts? I want to listen to the answer and grade from that.

This will help build the habit of focusing on producing the correct sound and avoiding reliance on pinyin.

No, but you could try just saying the answer, then pressing the audio button and grading yourself on that--no pinyin required before grading happens. On the web app, you can press 'A' for audio, too.

Oh, right--that keyboard shortcut won't work while you're typing, so you'd have to click on the speaker button during a pinyin prompt.