This company aims to provide modified iPads to prisons and jails. SF county has signed onto the scheme: http://apdscorporate.com/
This company already has a heavily locked-down tablet and provides a way for relatives to buy music for or send email or donate money to prisoners: http://blog.jpay.com/mini-tablet-for-prisons-now-available-i...
Victims' rights groups are not very happy about this: http://www.usatoday.com/story/news/nation/2013/08/17/tablets...
EDIT: I mentioned a scheme in Ohio, but associated it with the wrong link. That state uses Jpay, not the APDS system.