on an alleged email Steve Jobs sent to one of their readers. The email was in response to a complaint that AT&T is not offering a tethering option for the iPhone, even though it is offered on other smartphones as a $30/month add-on. The response acknowledged Apple and AT&T were discussing the option:
We agree, and are discussing it with ATT.
'Tethering' allows users to connect their laptops to the internet by using their mobile phone as the internet connection. The lack of a tethering option for the iPhone was highlighted recently due to the enormous interest in Nullriver's Netshare application
which was temporarily available through the App Store.
As mentioned above, AT&T does offer an official tethering option for many of its smartphones as an additional $30/month charge.
iPhone 6s (2015)