Learning the alphabet is a big milestone for every child and My A-Z for iPhone is one of the many options out there to aid in your child's learning. What makes My A-Z unique is that you can customize the alphabet to contain photos of things your child already knows.
For example, one of our family dogs' name is Ally, so for the "A" card, I have personalized it to spell Ally, show a picture of Ally, and recorded audio of my voice saying "A is for Ally". Even though my daughter is a bit young for learning her ABCs, she still lit up when she saw a picture of her dog on the screen and said "ruff ruff!"
You aren't just limited to a single photo, however. My A-Z let's you create as many cards as you want for each letter and swiping up and down will cycle through the cards. Swiping left and right will cycle through the letters.
I think My A-Z is a fantastic app to aid in teaching your children the alphabet and adds a fun, personal element to the process. The only thing that would make it better is if it was a universal app for the iPhone and iPad.