The puppy is cute enough, and the animations are quite good. Left to herself (taking a guess on the gender), the puppy will trot around a small room, scratch the floor, bark a little and generally be a puppy. Once in a while it'll get bored and yawn in a very cute manner. According to MASQ Interactive, you should have control of the camera, but all I could do was spin the camera. There's not very fine camera control in swipe/panning or pinch/zooming.
Aside from loose camera controls, the app is quite simple. You can tap the puppy to make her sit, lie down, stand up. I was able to make her sit, then a swipe made her roll over. I was then able to "rub" her belly, causing little hearts to pour out in a blatant attempt for more affection. I couldn't find much more interaction outside of these simple tap-and-rub actions and the three on-screen buttons. There's a button for "washing" the puppy (a gentle rain appears and afterward the puppy shakes it off). There are buttons for changing outfits, although you're just tapping through the options, not choosing them directly as in SuperPoke Pets [App Store link]. Lastly, there's a food button which makes a dish of slop appear. The puppy is a noisy eater, be prepared. Oh, there is one more thing: you can shake the iPhone and flowers fall around the puppy. It's pretty pointless.
So is all this worth $.99? If you're looking for a simple diversion for kids or you just can't resist having a Chihuahua in your pocket, then yes. If you're looking for a virtual Furby, then probably not. At least, not now. MASQ seems quite intent on (as they say in their description) releasing updates every two to three weeks until "everyone are 100% satisfied" (sic). Perhaps in a few weeks you'll be able to put a leash on the thing or whack it with a virtual newspaper. Until then, it's a very simple, if cute, "pet" app.