"Human Body Quiz" is an educational game designed for iPhone users. This game allows players to test their knowledge about the human body by guessing letters to complete body parts, organs, diseases, and anatomical features. With each level guessed correctly, players unlock a unique encyclopedia with photos and descriptions of each challenge.

One of the standout features of this game is that it does not require any real money to purchase hints. Instead, players can freely use in-game coins, which accumulate automatically at a rate of 2 coins per minute. Furthermore, there are no penalties for incorrect answers and no time restrictions, allowing players to think carefully before responding.

The game offers a total of 300 challenges that can be completed for free, although players have the option to purchase in-game coins to show their support. For those who prefer a faster progression, a premium mode is available for a monthly subscription fee, which offers unlimited access to the game's content. This premium mode can be tried for free for three days before committing to the subscription.

Please note that "Human Body Quiz" utilizes an auto-renewable subscription model for the premium mode. After the initial three-day free trial, the subscription automatically renews every month unless canceled at least 24 hours before the end of the current period. The cost of the subscription is $2.99 per month. Users have the ability to manage and cancel their subscription through the iTunes & App Store settings.