Just, freaking, awesome!
The first thing I should mention about this game is the souls. Every so often after killing a a certain monster you will get their soul. These souls can be equiped to provide you with different abilities and can be combined with weapons you find throughout the castle to create more advanced weapons.
What this game lacks in difficulty it makes up for in exploration. While more traditional Castlevanias are very hard and the goal is simply to stay alive, the place where this game's challenge lies is in exploring every area of the castle and unlocking every soul and weapon along the way. This makes for a very lengthy adventure.
This is just is an awesome game. Even after playing several other Castlevanias, this remains one of my favorites. While the Touch screen controls are a little weird, the game in a whole is a great addition to the Castlevania family.