A Tor client on the App Store,
Tor Browser, is actually a fake app saturated with adware and spyware, according to complaints. The app is
said to have been reported to Apple in December; at one point the company suggested that the app's creator, Ronen, would be allowed to respond, but no news has emerged since, and the app remains on sale for $1.
The App Store review process is normally supposed to screen out fake and/or dangerous apps. Sometimes they survive screening however, and may only be removed once enough media attention is drawn to the offending apps.
Tor is a platform based on network relays that allows users to maintain anonymity while surfing the Internet. While it is sometimes used for illicit activities, the privacy it enables can be essential for people legitimately worried about government or corporate surveillance.