Quote: "What (kind of) camera should I use? Can you recommend one? "
Quote: "And is it better to make an animation from a movie or from a series of photos?"
AGk animation is still limited to sprite animation where you have multiple images joined together or, you can join them manually and then, play those images in the sprite using sprite animation commands.
images must be ".PNG",".JPG" and it is advised to make it small as
most mobile platforms have limited memory.
my advise to you is don't care much about the camera type. you're better off with a design software.