Ever since I had a smart phone, people are unable to clearly hear me, is this normal?

I always start to have issues with people hearing me when I had any smart phone from android, windows phone to iphone, iphone being the worst.

Any suggestions?

(Currently I have a iphone and still people have difficulty hearing me over it, I went to the apple store and they de-clogged the voice speaker where there was dust jammed up in there.)

Added (1). that was just a temporary fix now people still can't hear me

I have 1 buddy that I can't hear and it's definitely his phone because I've hear other friends complain about not being able to hear him.

Maybe try using the speaker phone.

Learn how to speak up.

Special cleanliness