My Sun Conure does use her feet as hands all the time. She is able to pick things up to eat, or examine. He also uses her feet to scratch his head.
Two things that I have notice that she does with her feet that I have never seen other birds do is to use a cell phone. She dials the number but I have to hit the call button because it is in the middle of the phone and she can not reach it with her toes and grip the phone enough to push the button. She only says "hello and Connie" but the people she calls know it is her.
She also likes to play the piano when she first gets up in the morning, she sometimes plays for hours. You should see her, she is so cute, but it is sad too. She plays chop sticks and she can get the first part just fine, the part where you keep pressing the two keys that are right together, but when it changes and you have to push keys that are not next to each other she has problems and gets very frustrated. She cusses and uses the F word when I am not in the room because she can not get to the next part of the song. I just pretend that I have not heard her cuss but I know she is very unhappy about it.