A:
No apps for the Simple Touch. However, there is also very limited web or social media access on it as well in it's natural status.
The web is in the form of access to the Barnes & Noble bookstore.
The social media is linking to twitter or facebook accounts. It seems to be about posting what you've read, but it may be more in-depth than that...I have NOT linked my Facebook to find out.
Easiest way around it? Don't give the kids the wifi password, and don't save it when you DO use it. That way they have no wifi access via the nook whatsoever...unless they come to you and ask to buy a certain book. Then you can turn it on...give the password, make the purchase, then turn off wife & click "forget network" afterwards.
Beyond the seeming small Facebook & Twitter linking (the descriptors only indicate it's for posting about what you've read) and the possibility of buying too-mature books...there are no other needs for parental controls....and that's managed by simply not giving the wifi code at home.
Unless you root the device. Then parental controls are needed & available.