I don't have a nanny cam but we do have exterior cameras setup on the outside of our house. We bought them from Costco and they can be viewed from your phone or any computer connected to the internet. They were very easy to install.
http://www.costco.com/Q-See-8-Channel-Security-System-with-500GB-Hard-Drive-and-8-High-Resolution-Cameras.product.11652270.html
I personally would put one in the corner of the baby's room, and ones in whatever areas she would spend most of the time with the baby.