When I last searched there were 191 audio recording apps available on iTunes. These type of apps can be cute, such as Chippy Talk, or a bad dude like Talking Fred.
The common denominator among these apps, in addition to their audio recording ability, is their interactivity with the user. Touch the animal, person, robot, or some other creature and it reacts by moving its body or a body part, changing it’s facial expression, making some kind of noise, or any combination of the aforementioned. Some of the apps let one feed the creature or give it an item such as a balloon. These are fun apps and high on the scale for child entertainment.
I used these apps with a nonverbal, severely autistic boy. I was hopeful that the immediate feedback of hearing his voice would trigger an understanding of the importance of oral communication (cause-effect: the child makes a noise and it causes the image on the screen to repeat exactly what was said). The child loved the app but, unfortunately it did not result in a the aha moment I had hoped for with this child.
These apps can be tried with selective/elective mutism as a starting point for therapy. I can see such an app as a means to getting a child to start communicating.
Because the automatic audio replay distorts the user’s voice, I would not use these apps for sound production feedback. If the screen’s character is a chipmunk, the user’s input is repeated in a chipmunk voice. Plus the replay is not always a clear reproduction.
Search “talk free” on iTunes to bring you to these apps. Most of these apps are free.