There was a time when tethering — or using your iPhone as a mobile hotspot to share data — was more complicated and expensive than it is now. That lead some developers to create apps that allowed users to circumvent carrier side tethering fees.
Some of those apps included iTether, Handy Light and NetShare. While all of them were initially approved by Apple’s review process, they were also all later banned by Apple in the early 2010s. Why? Apple says that the apps “burdened” the carrier networks.