My First Puzzles: Alphabet

Some qualifiers:
We have many of the "My First Puzzles" apps and love them.
Our account is password protected so you have to enter the password (that is too complicated for our 3yr old) for any app purchase or update.

I downloaded this particular app "Alphabet" for free today for my 3yr old to play. While sitting with her and watching over her shoulder she completed all the letters of the puzzle. It had A, B, C, H, I, J, N, O, P, U, V, and W as individual puzzles and then grouped puzzles for DEFG, KLM, QRST, and XYZ. So a total of 16 puzzles. She completed them all immediately. While monitoring her every move it never once asked to purchase any additional puzzles or add-ons. When she finished the puzzle I even went to "more games" to see what others she would like for free. When I clicked on others it took me straight to the app store (without a charge). An hour later I noticed a charge to our online banking. After double checking the apps I had purchased today I called the "App Store Representative" to find what this charge was from. 40 minutes later and her showing me how to find where the charge came from, it came do to "an in-app purchase". The actual app was free but there was an "in-app purchase" from the app. I would have to contact the app developer. When going back to the app description to find contact info it was then I read the reviews. That was my fault in not researching it, but weve always had great success with the other "My First Puzzles". I also noticed in reading the App information more closely I found a section labeled "Top In-App Purchases" that read "1 pack of 12 additional puzzles for $1.99." We never recieved additional puzzles so I guess it meant we were charged for the puzzles she played within the "free" app. So the $2.18 charge I am stuck with however it was not alerted in any way during the game play. However in talking with the App Store Representative I learned how to block future "in-app purchases." If you do not know how to do that, here are the steps:
1) Go to Settings
2) Click on General
3) Click on Restrictions
4) Enter your 4-digit passcode
5) Scroll down to "Allowed Content" section and change the setting for "In-App Purchases" to OFF.
The reason Im giving it 1 star is because it was purchased as a free app but had a hidden built in charge. I like the app, not the dishonesty!

Very Observant Mom about My First Puzzles: Alphabet - A Free Educational Puzzle Game for Kids and Toddlers for Learning Letter Shapes - Kid Toddler App