Aside from taking out the headphone jack, Apple also revamped the home button in the iPhone 7. Instead of having a mechanical button, a force sensitive static button is in its place. And at times it might not work. But there seems to be a workaround for that. A MacRumors forum user found that the iPhone 7 displays a home button on the screen when it sees there’s a problem with the button.
According to the user, the message showed up when the phone turned off while it was charging. When he restarted the device, he said “it worked at first then started spazzing out. The Haptic engine kept firing [three to four] times in a row for every ‘press’. I restarted [the phone] again and it’s back to not working.” With Apple supposedly planning to remove the button entirely for the 10th-anniversary iPhone, this might be considered as a precursor for that.