The tablets, developed by a company called American Prison Data Systems, have been specially configured, both physically and technologically, to ensure inmates can only access four secure websites — including a law library — as well as a calculator, an educational application and a secure repository of educational curriculum developed by Five Keys.

http://www.sfgate.com/politics/article/S-F-jail-inmates-to-have-access-to-computer-5838236.php#photo-7030684