Well, you get open, clear, unencrypted internet access.. But probably no torrents, no PGP, probably no bitcoins (and you wouldn't want to, someone will steal your coins).
However much like the use of mobile phones in prison, internet access without supervision, via a smartphone, is banned for all inmates.
In Canada, inmates are not allowed internet access.
In the Philippines, prisoners are allowed to surf the Internet while closely supervised.
In the United States, the Federal Bureau of Prisons, an agency of the U.S. Department of Justice, has put into place the Trust Fund Limited Inmate Computer System (TRULINCS) on February 19, 2009. This allows inmates access to electronic messaging through e-mails. The message must be text only, and must be conducted in a secure manner between inmate and the public. Messages are subject to monitoring.
Now, for education purposes, for legal viewing of shows or movies, fast internet would be nice. But don't expect any kind of privacy.
I would read up and soak news, current events, read some forums (but probably can't post, just lurk.)