Apple is under fire for an app sponsored by a group called Exodus International that says it can cure homosexuality through prayer. Apple vets each app individually so the controversy is centered around why they allowed this app, which many are complaining is offensive and homophobic, while banning other apps that are racist or anti-Semitic. Online petitions are currently circulating. Apple has removed other apps perceived as anti-gay in the past after objections were raised.
As of this posting, the app is still live.