First, I'd like to say that deadly dungeons is awesome and shows great potential!

I'm not sure this is a bug, but I'll post it here anyway.

Using the UI arrows it's possible to move faster than the movement animation is showing; simply hammering the forward arrow will make the player swoosch along at break-neck speed. Is this the intended behaviour?

Tested device: Samsung Galaxy S, Android 2.2.

Yep, being able to move as fast as the player wants is the intended behavior.  Other dungeon crawlers of this type have similar behavior.  This gives the player a better ability to choose their positioning and prevent themselves from getting surrounded.  Getting surrounded usually means the player is going to die.

The player may find that some creatures are quite difficult too.  Without the right skills and abilities (available in the next beta), a player will find it hard to just stand there and take the punishment.  Being able to move as fast as they need to allows them to run away to heal or lead the creature into a position that gives the player more advantage.

You may want to check out some YouTube videos of Dungeon Hack.  Deadly Dungeons has a similar movement system as that game.