How does a calling card work if i send it to my husband in jail?

my husband in jail, if i send him a calling card how does dat work? will they charge me? can he keep it in his cell? how bout pictures? can he keep pictures of our new born baby girl ? or will they take them from him? i was told that he couldn't cause he can use it as a weapon within time. is it true? or can he keep em? can i smuggle him a cell phone? if so how?