Ask Slashdot: An Android or iOS App For Boosting the Volume of Speech-Impaired Person?

dryriver writes: A relative of mine has been left with extremely low speech volume -- about 25% of a normal speaker -- and lack of high pitch capability after a major throat surgery. He cannot speak on the phone at all now -- you cannot hear him properly on the other end of the line, even though you can understand his speech OK when you are standing in the room next to him. Is there an assistive Android app that can:
1. Significantly boost the output volume (e.g. X 4) of the Android phone microphone he speaks into.
2. Add voice box, equalizer, autotune or audio filtering/bass boosting type audio effects in realtime to the microphone input to fix the speaker's pitch.
3. Can filter out background noise to some extent (so it doesn't get boosted as well).
4. Allows these effects to be used easily during phonecalls?
All the Android microphone/equalizer/megaphone type apps I've tried so far have huge problems -- some are novelty voice-changer apps for teens, some demand ridiculously broad permissions to everything on the phone including realtime location data of the user, some demand that an external mic is attached to the phone, some are too simple technically to do anything useful and some are advertising-fests that are plain unusable. Is there a good Android -- or iOS -- app for the speech impaired that would give this person a chance to make audio phonecalls on a smartphone again? Thanks for any advice!

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